I gotta disagree. If they release 'Strawberry Shortcake with sunburn' it's going to suck outloud. If a new player picks up a craptacular product he doesn't get interested in the original material, he wonders why anyone bothered to reprint crap.
Well of course there are limits. But let's say they release a really happy, heroic game in a desert, like you suggest.
Those who are old-timer Dark Sun fans know it's crap. You and I do little more than pilfer it for monsters, and run our old Dark Sun games.
Those new guys, though, many will think "it sucks" and leave it at that. But it doesn't stop there. There will always be people who check things out - and that means new "recruits". It means more people talking Dark Sun (I'm really looking forward to that - I'll be able to go online and see a bunch of new Dark Sun posts!). It possibly means more third party support for Dark Sun (maybe they won't call it "Dark Sun", but I'm sure we'll see some "savage desert" books come out next year, just like when Eberron was released we saw more Steampunk books hit the shelves).
Right now, Dark Sun is a dead setting. It saw a few releases for the entire 3e era, and they weren't "true" releases that could really stoke fan interest too much. But they still got people buying back PDFs, and talking.
When they remade The Day The Earth Stood Still, everyone knew it was a garbage movie. But people still talked about the original... and how many people do you think watched the awesome original, having never thought about it before?
And let's be honest. They're not really going to screw up Dark Sun that bad. There will be a lot to it that is awesome. The write up for the Mul, Thri-Kreen, and Half-Giant is going to be fine. There will be cool new feats. The monsters will be plentiful, and cool. New Psionics will probably be there. The map will be pretty. I'm sure we'll have easy-to-use, cool defiler mechanics.
In other words, the future is bright for Dark Sun. (There's a joke there, but I'll let you make it).