No McFarlane Toys, IMHO. D&D needs stuff for kids to play with, not for adults to put on a shelf.That would be interesting, especially if they contracted McFarlane Toys to create them. http://www.spawn.com/toys/
The Dark Sun comic was a mini.There are already D&D comics being published by IDW right now. They are nothing special but fun to read. One series for Dark Sun, and another two set in Forgotten Realms.
The Dark Sun comic was a mini.
There's one series set in the default 4e world, a Legend of Drizzt mini and an upcoming FR series co-written by Ed Greenwood.
A cartoon.
Transformers was started as a cartoon and now look at it. There is precedent for a D&D cartoon already so it's not a stretch to entertain the notion that it could be done again.
If it's done WELL, as in it's a decent cartoon with a decent story, decent illustration, decent characters, etc. and it's aimed at the young adult market (which is a bit of a misnomer because although technically a 'teenage' bracket, younger kids want in on what's cool for the older kids and parents tend to enjoy it as much as their kids and geeks of all ages tend to embrace it as well), then it could be huge.
It would also need to be done cleverly. There would need to be tie-ins to the D&D P&P game within the actual story. But it would have to be done in a way that's not obviously just a gimmick to push product. It would have to be done in such a way that was very well thought out and considered from many angles rather than just some writers brain-storming story concepts.
This would lead to all sorts of extra products. Figures, graphic novels, novels, collectibles and even a movie (that didn't totally suck). All the while growing the D&D brand and P&P game.

(Dungeons & Dragons)
Rulebook featuring "high magic" options, including a host of new spells.