Parableman lists these as forthcoming commentaries on James. I'm mostly looking forward to Allison, McKnight and Witherington. Joel Green may surprise me, I hope but Kloppenborg probably won't.
Dale Allison (ICC) - it will be good to see how Allison handles the echoes of Jesus' teachings in James.
Bill Baker (Two Horizons NTC)
Daniel Doriani (REC)
Timothy George (BTCB)
Joel B. Green (NT Library)
John S. Kloppenborg (Hermenia) - how has James appropriated the 3rd strata of "Q"? Or is James the source of "Q"?
Dan G. McCartney (Bakers Exegetical CNT)
Scot McKnight (NICNT replacement) - What exegetical insights will McKnight bring to the table? A New Vision for Israel perhaps? (cf. Jas 1:1)
Ben Witherington (Letters and Homilies of the NT, fall 2007) - Sapiential Sage?