Well, with CHDK you could actually do 64 sec exposures
Any waaaaaay more. Automated bracketing, scripting for timelapses, motion detection, live histogram, zebra mode, Edge detection, RAW file (Even saving as DNG), Shutter speeds up to 1/50.000 of a second, Remote release over USB, printing custom lables directly on the images, Advanced bad pixel removal, in camera RAW processing (Substraction, addition, averaging..) .. and a lot more.
-> A lot of cool stuff no other camera can offer. I'd strongly recommend to stick with the SX10 & Wait a few months. But thats just my spoiled opinion as a canon (and chdk) fanboy.