Here is Sam Waldron and Rich Barcellos on this-
New Covenant Theology is a technical term referring to a theological view of redemptive history primarily found in Baptist circles and contrasted with Covenant theology and Dispensationalism. It has been assumed that one has only two primary options in understanding the structure of the Bible in evangelical Christianity -- Covenant Theology (coming out of the Reformation) or Dispensationalism. However, proponents see what has come to be called New Covenant Theology as middle ground with a biblical basis of understanding.
Proponents maintain that the primary thrust of New Covenant Theology is the recognition of a promise-fulfillment understanding of Scripture. They suggest that whereas “Dispensationalism cannot get Israel and the church together in any sense whatsoever, and Covenant Theology cannot get them apart” (Reisinger, 19), New Covenant Theology finds the realization of all that the Old Covenant typified in the New Testament church (Covenant Theology, in contrast, merely levels the playing field and identifies them for all intents and purposes). The Mosaic economy is viewed as a temporal, conditional covenant that has been forever replaced by the glory of the New Covenant (2 Corinthians 3).
Despite its seemingly recent representation in modern theological discussions, today's proponents of New Covenant Theology (NCT) see roots extending back to the post-Reformation theological developments. Baptist history, especially the Reformed variety, is rooted in the basic tenets of New Covenant Theology. Much of its primary teaching is reflected in the influential First London Baptist Confession of Faith, especially in its 1646 edition (which is held by many New Covenant Theology churches today). However, in the historical whirlwind of this period, Calvinistic (Particular) Baptists felt a need to show close alignment with their Reformed brethren^[citations\ needed]^ in the Congregationalist and Presbyterian churches in order to avoid persecution and thus adopted the Second London Confession in 1689, a virtual restatement of the famous Westminster Confession with slight modifications, especially, of course, in the area of baptism. This move left an indelible mark of "covenant theology" in the Particular Baptists from that point forward.
The last twenty-five years have seen a great resurgence of Reformed theology in Baptist circles. As a result, many within this camp have sought to develop a more clarified system of the covenants that relate back to older thought. Leaders of this movement include such theologians as John Reisinger, Jon Zens, Peter Ditzel, Fred Zaspel, Tom Wells, Gary Long, Geoff Volker and Steve Lehrer. The writings of Douglas Moo, Tom Schreiner, and D.A. Carson on the relation of the Christian to the law reveal their sympathies with NCT. However they have not wanted themselves to be so labeled.^[citations\ needed]^ John Piper also has many points of contact with this movement, but an article at Desiring God carefully distinguishes his position from the Covenant, New Covenant and Dispensational theological systems. 
Contrasted with Covenant Theology
New Covenant Theology, while having some similarities to Progressive Dispensationalism has more in common with classic Covenant Theology, in particular in how Israel and the Church are viewed. Both sides do not see an absolute distinction between the Old Testament people of God (Israel) and the Church as Dispensationalism does. They also are similar in their soteriology and eschatology (some see literal millennium and some don't, but neither would hold to a future millennium for the reinstatement of Israel as in dispensationalism).
There are points of contention however. New Covenant Theology has more in common with Dispensationalism than Covenant Theology in terms of the relation of the Mosaic Law to the New Covenant economy.
The Church has become “spiritual Israel.”
Gentiles are heirs to the Abrahamic Covenant (Gal 3:8–9; Eph 2:11ff; Rom 4:1–13; Rev 5:9).
Acknowledges the redemptive-historical hermeneutic.
Calvinistic in soteriology.
The Old Testament does have prophecies of the Church age (Jer 31:31–34; cf. Heb 8).
God’s main purpose in history is Christ and His Church (elect throughout all ages).
Everyone ever saved is saved by grace alone, through faith alone, in Christ alone (Rom 4).
Christ offered a spiritual kingdom to ethnic Israel but was rejected. Spiritual Israel, however, accepted and continues to accept the kingdom.
The Church started at Pentecost, and there is therefore no “Church” as such in the Old Testament/Covenant.
Rejects the three “theological covenants” often espoused (with some variation) in Covenant Theology, viz. the covenants of redemption, works, grace.
Sees the Mosaic Law as only a means of blessing in Canaan.
The Mosaic Law is fulfilled with the advent of Christ and the New Covenant; New Covenant believers are under the Law of Christ (1 Cor 9:21).
All hold to credobaptism.
The Holy Spirit worked differently in the Old Covenant than in the New (the Spirit now indwells believers).
The biggest difference between classical Covenant Theology and New Covenant Theology is how they view the Mosaic Law. Covenant Theology sees the Mosaic Law as divided into civil, ceremonial, and moral, with only the moral law remaining in effect. New Covenant Theology sees the New Testament writers as referring to the Mosaic Law in its totality (in other words all 613 laws, not only the Ten Commandments). Therefore, when Paul says that "we are no longer under a tutor" (Gal 3:25) he is saying that the Mosaic Law en toto has passed away.
There is still a Law in the New Testament however. Paul says that he is "under the law of Christ" (1 Cor 9:21), and he is therefore still responsible to Law. The eternal, unchanging moral law is expressed in both the New and Old Law, but the Old Law doesn't itself carry over. The Law of Christ are the moral commands given by the writers of the New Testament (Jesus and his apostles). As Moses went to a mountain to get the Law, so Christ went up into a mountain to give the new Law (Mat 5-7; cf. 2 Cor 3).
Detractors, like Reformed Baptist Sam Waldron, see New Covenant Theology deviating from the traditional Reformed hermeneutic of the law which argues that whatever is not abolished in Christ continues. For example, in Waldron's assessment "New Covenant Theology says that the entire Law of Moses has passed away and only remains in so far as it passes through the hands of Christ. According to Wells and Zaspel, prior to Christ’s actual teaching in the New Testament one simply cannot be sure what He will do with the law of the Old Testament. Thus, none of the Law of Moses or even the Ten Commandments remain binding for us unless Christ hands it on to us in the New Testament." 
Reisinger, John G., Abraham’s Four Seeds, (Frederick, MD: New Covenant Media, 1998).
Tom Wells and Fred Zaspel, New Covenant Theology: Description, Definition, Defense, (Frederick, MD: New Covenant Media, 2002).
Wayne G. Strickland (editor), Five Views of Law and Gospel, (Grand Rapids: Zondervan, 1993).
Richard C. Barcellos, In Defense of the Decalogue: A Critique of New Covenant Theology, (Winepress Publishing, 2001).
What is New Covenant Theology
A Brief Explanation of "New Covenant Theology" Fred G. Zaspel
"But I Say Unto You" John Reisinger
John Piper's view (Agrees with NCT on Law)]
History of New Covenant Theology Kevin Hartley
How Does the Christian Relate to the Law of Moses?
A Comparison of Three Systems by Donald Hochner
"A New Covenant Critique of Dispensationalism" Ragan Ewing
Covenant Theology vs. New Covenant Theology Tony Warren
New Covenant Statements of Faith:
The New Covenant Confession of Faith
The Statement of Faith for Christ Fellowship of Kansas City
Critiques of New Covenant Theology
New Critique of New Covenant Theology
Responding to Criticism
In Defense of the New Covenant: A Theological Response to Richard Barcellos’ Book, In Defense of the Decalogue: A Critique of New Covenant Theology