Ok. So I have now done a semi-review of the Dark Sun materials, and I would think that you could summarize the OP as such:
* All Dark Sun themes, setting-specific rules like arcane defiling, and other optional rules for that setting.
The feats almost all have themes or other campaign-specific prereqs, so they're not really an issue (hooray for a good design decision there!). The races are, in my opinion, totally ok. I think you may need to re-flavor them a bit, but half-dwarves seem completely cool and mantis-people are ...well, a challenge, but if you can have swarms of intelligent shards of crystal, I think 4-armed mantis people are hardly a stretch. Fresh coat of paint... bam. (Heck, they could be 4-armed warforged pretty easily.)
Some of the new optional character builds - like the new warlock pact source twils mentioned - are certainly different, but mechanically I don't think they're too worrisome. Re-skin them and I doubt it'll be a big deal. I wasn't able to check every single one in depth, so there may be an exception here or there, but on the whole I think it's ok to leave them be and just come back to exceptions as they are found.
The only other areas that I think might raise some eyebrows are the new weapons - pretty much exclusively superior, so they cost a feat anyway; don't think they'll be too bad - and a couple of magic items. Of the magic items, I see "carnage" weapons as being the only one that struck me as worth taking a close look at, although obviously my standards are not representative of the board as a whole. Otherwise, I think the mechanics of the book aren't something to be scared of. The campaign world is decidedly low-magic, so once you exclude the crunchy things included to make up for that (themes, other optional rules like wild talents), the rest is really pretty par for the course.
I think it's worth being specific about the Dark Sun themes as opposed to just themes; as CaBaNa said I think that's a new direction they will like and expand on in other materials (sort of a "paragon path lite") and so we shouldn't just discount them as a whole just yet.
So in summary, I will vote YES as well to the OP, and suggest the wording I have above (although that's not conditional to my vote). I would also suggest the two races and other crunchy bits be left as "ok", so long as they are skinned appropriately. If someone sees something specific that seems amiss, we can take it up in another thread. (And someone other than me might want to take a look at "carnage" weapons.)
(Also, as a complete personal aside, I noticed that the WotC copy-editing standards - which are absolutely horrid and have been since just before 4.0 was released - have not changed. I counted at least two instances of "see page xx". Seriously, guys?)
