The official release of Capture One 3.7.4 (in PRO, LE and DB flavours) is slated for April 20, 2006, says Trine Voss, VP for Sales and Marketing of the software at Phase One, and will be a free update for licensed users.
Faster image processing and support for the RAW files from several new camera models - including the Canon EOS 30D - are the main changes in the upcoming new version for both Mac and Windows. The Mac version will ship as a Universal Binary, which means it will contain native code for both Intel and PowerPC Macs.
Version 3.7.4 is available for testing now in release candidate form from the downloads section of the Phase One web site. A press release has additional information about what's new.