(Not knocking anyone who likes them, this is just my opinion)
I saw them play on SNL once, and my god they were horrible. Other than that, haven't heard much of their music. Based on what I saw and the hype that's going around about 'em, I'd have to say they're very overrated. They're no more "saviors of modern rock" than those whiney bands like "A Simple Plan".. you know what I mean, those bands that sound like they put a 14 year old boy in front of the mic.
I'd rather have hair metal back than half the crap that's out now. I can't even explain it.. but like The Hives (or the Vines?), The White Stripes, all those bands... it's like they're trying to be all artistic and poetic, but they really aren't.
Saviors of modern rock would be Tool. They're mainstream, yet at the same time I don't feel like they're getting enough credit. They pretty much are a modern day Nirvana. You can't get any more original than what they do. They're just on such a completely different level than everything else.
The next "official" Nirvana/Led Zeppelin/Beatles should hit any day now... but as for The White Stripes, eh, I think it's safe to say that they definitely aren't one of those bands
Those type of influential bands that are powerful enough to change an entire industry usually come around once the music industry is a complete shitstorm (like it is now, and like it was back in the early 90's).