It really cannot be said enough how screwed up this is. Muse has headlined in the States already, and sold out most of their shows. How in hell can anyone possibly justify having them open for anyone, let alone a shitty band like My Chemical Romance? I've gone to shows specifically for openers before, perhaps never even having heard the headliner, but I've always stayed for the entire show. In this case, however, I can easily see myself going for Muse and then getting the hell out of there.
Muse are positively brilliant, simply put. Matt Bellamy is one of the most amazing guitarists in modern rock. And they're ridiculous live. Getting hit with "Stockholm Syndrome" at the end of their show was one of the most badass concert moments I've ever experienced (they usually end with that, I think). And their headlining set at Glastonbury is one of the best concert recordings I've ever heard. Their last album was slightly disappointing, but I still like it. Origin of Symmetry and Absolution are both incredible albums, though, and to whoever called Showbiz a dud, I actually really like that one.
I will also have to admit, however, that My Chemical Romance are slightly better than the rest of the emo-punk crap out there. I actually find their single listenable, which is more than I can say for most other bands like them.