Orcus said:
You cant skip the MM It looks too awesome, and has too many core monsters.
Pfft, I'll get 'em all on the D&D Insider Rules Database.
Everything else you've posted makes me think that you guys might be the reason I go over to 4e. You're addressing all the concerns that I have with WotC's apparent monster philosophy, which is one of my biggest sticking points so far. It's always possible that the appearances are decieving, but I like that you guys are deliberately taking a compatible but slightly "richer" take on a monster book.
Mudstrum_Ridcully said:
We don't know yet how much fluff text the MM contains.
Well, we do have hints. The bodak/boneclaw page, for instance. That's part of what's giving me a sinking feeling about 4e monsters. Seeing the bodak's eerie compelled evil against the will of a barely-sentient soul still trapped within it turned into "kills because it likes killing" is pretty disappointing, like the 4e team thought that the only interesting part of the bodak was it's death gaze. The stats probably make for some fun encounters, and the rest of the fluff sets up future encounters pretty well, but the bodak would probably function more rewardingly for me as an elite or solo creature with that "slight twinges of memory" aspect than as a soldier in the shadow army of nightwalkers.
I think for a core book, I want as much material to work with then possible.
I'd agree, but the material I need is more than just sweet stats.

I need sweet stats, but I need monsters that exist beyond the five rounds you kill them in. Which is why a "monsters are more than just XP speedbumps" philosophy is very resonant to me.
It looks like each standard MM entry is a single page, with the stats for a version or two on each page, along with a kickin' picture and a blurb of text. Humanoids and dragons and beholders and illithids and other prominent baddies probably get more versions and more pages.
From the sounds of it, the new Tome will have quite a bit more in the way of inspiration for the use of these monsters in roles other than "Adversary."