Yesterday I submitted a review of Thomas Schreiner's commentary on Galatians for the Journal of the Evangelical Theological Society. Hopefully it should be in print before too long. Here I wanted to offer a three quick assessments about the book.
First, the layout in the series as a whole is a step up from traditional commentaries. Zondervan has made some great choices about what to include in the commentary and how to include it. For example, each section of the commentary has a clausal layout of the passage. That's a great way to see the structure of the passage. There's a lot here above and beyond simple prose explanation of the text.
Second, Schreiner writes from a traditional reformed perspective. He does not accept the New Perspective on Paul. His exegesis of key texts (like Galatians 2:15-21) and various excurses throughout offer a worthy defense of the traditional interpretation, namely, that Paul is indeed arguing against adherence to the OT law as a requirement for salvation.
Third, Schreiner's style and content are crisp and brief, perhaps too much so. There are lots of places where a fuller discussion would be helpful. He has done a lot within the allotted space, though, and despite the brevity the commentary covers a lot of ground very thoroughly.