The rest of Sony's DSLR refresh—the more expensive part—is here, and it's slight. Their midrange A5x0s get new, low-light-happy Exmor sensors and automatic HDR shooting. The full-frame a850 is almost exactly like the a900, but nearly $1000 cheaper.
The a500 and a550, only differentiated by their 14.2 and 12.3-megapixel sensors and the 550's slightly faster shooting speed (7 per second), inherit some of the same sensor and noise reduction technology as those Exmor-equipped point-and-shoots that David Pogue liked so much, meaning that they're probably pretty good at shooting in the dark, though the claim that you can snap pictures at ISO 12800 "without sacrificing fine detail" is a little tough to swallow. Both cameras also get an easy HDR mode, which handles processing in-camera in a matter of seconds, and a new set of storage options: Compact Flash is out; Memory Stick and SDHC are in.
And no, even though they clearly should, neither shoots video.
The a850, as suspected, is more or less a carbon copy of Sony's a900 full-frame DSLR. That's the same 24.6-megapixel sensor, and what looks like the exactly same body—it even claims full accessory compatibility with the a900. The only noticeable difference is that the a850 will run just under $2000, in November, for just the body, making it a decently cheap option for someone with a bunch of Minolta glass laying around, and a hankering for a full-frame DSLR.
The a500 and a550 will ship for a decidedly less exciting $750 and $950, body-only, in October. [Sony]