A cluster of worthwhile commentaries on the Corinthian correspondence are due out this fall, headlined by Gordon Fee's revision of his classic 1 Corinthians commentary (NICNT).
Fee's preface to this updated edition can be read in its entirety here.
Another volume to keep an eye out for is Mark Seifrid's contribution of Second Corinthians in the Pillar series.
Seifrid reads 2 Corinthians as a unified whole and believes that the main issue that Paul addresses in the letter is the
Seifrid's volume is due out at the end of September. For all of those attending SBL Annual, it will be worth making room on your bookshelves for these volumes.
I would be remiss not to mention the excellent commentary by Raymond Collins (Paideia) that debuted early last summer. I am planning on an interview with him about this volume soon.