If you don't log in to KDE and run a KDE app from GNOME, then you don't get Bluecurve as your theme for qt apps.
Hmm, i cannot reproduce it on a fresh beta3. i think, you still have old kde config files in your home. please try following: add a new user, start gnome with this user and start e.g konsole. does it use bluecurve?
*** This bug has been marked as a duplicate of 74795 ***
Changed to 'CLOSED' state since 'RESOLVED' has been deprecated.