Yeah, there's a curious lack of AAing, which lead to some strange white artifacts around parts of the characters in earlier shots. But some of the more recently-released shots look a little better.
As far as I know, SADX will also be including 50+ extra missions (in the existing levels, but they could still do a lot with them) and an EGM article claimed there will be a different ending (beating the extra 50+ missions won't be required to see it).
The flood of titles does worry me a little, it's been kind of a trickle for the past few years with the exception of the Advance titles recently (which were outsourced to Dimps, at least the first one was) and the Adventure series, but suddenly we're seeing SADX, Pinball Party, Sonic Trick, Sonic Hero, Giant Egg, AND the supposed Sonic Next game that's actually supposed to be the next big followup (so what are Sonic Hero and Giant Egg? Both are claimed to be GCN-exclusive, and Sonic Next is supposed to be multiplatform). That's a lot of work in very little time. They've obviously already been at it for quite a while, and Sonic Team is big, but still, it makes you worry...
But do the names "Sonic Hero" and "Giant Egg" make you think of the Hero and Dark sides to SA2(B)? Do you think they've expanded the idea out into making two seperate games?