Because the mirror is fixed, both the A33 and A55 are more compact than many traditional DSLRs. But, in this case, smaller bodies don't mean smaller spec sheets. Both new Alpha cams can use the new Exmor APS HD CMOS sensor Sony is so proud of. The 16.2-megapixel A55 is capable of grabbing 10 frames-per-second, while the 14.2-megapixel A33 caps off at 7 fps. Plus, both can capture 1080i HD video (in AVCHD format, of course) using Quick AF, which is a boon for those transitioning from a dedicated video camera.