The A550, the higher-end of the pair, comes built with a 14.2-megapixel resolution sensor, a 921k dot 3-inch LCD screen, and a quicker burst option called Speed Priority mode. It's estimated retail price is $950.
The A500, estimated to sell at $750, will include a 12.3-megapixel resolution image sensor, a 230k 3-inch LCD screen and a maximum of 5 fps (versus the 7 fps on the A550).
One ground-breaking feature for DSLR models is the option of face detection in live-view mode. However, neither offer HD video capability, which is going to be a problem if they want to compete seriously with Canon and Nikon for the advanced DSLR market.
For a detailed, comparative look at these two cameras, check out the CNET review here.
Do either of this models pique your interest?