If the whole event was unplanned, yes, definitely classless, basically saying to Swift, "I'm happy you won, but you aren't nearly as good as Beyonce & don't deserve this award.." a big "F" you.
If it was staged, a) it was to get MTV more ratings that night...they probably knew people would be Tweeting, Facebooking, MySpacing (if anyone still even does that)about what had happened & thus getting more people to tune in. B) This is only going to propel Taylor Swift's career even more, and even though she is already pretty popular, it never hurts to get a little more push from one of the music industry's biggest stars today. C) Kanye's career isn't going to get hurt. Again, IF this was staged, it was meant to get his name back out there again...any publicity is good publicity. He will still sell albums, make guest appearances on other rappers'/R&B singers' albums. This will all be water under the bridge in a few weeks.