hm..... to be honest, I sort of hate it. Er.... actually, I think it may be one of the most-damaging legitimate jobs in existence. Mainly, I think that because of the turn that marketing has taken in the last few decades--it's all image-based and content-free, which then just sort of perpetuates (what I think to be) unhealthy cultural views. As the best example I can think of, take a look at Apple and the IPod commercials, where people are silhouettes and they dance around with flashy, colored backgrounds. There's not a single thing about IPods in these commercials at all... but they just get set up as "those things that are cool, for some reason."
The counter to this is my brother (business major, marketing concentration), who consistently tries to argue with me that not all marketing is bad. His first case comes if you have a product that's legitimately better than the competition, and need to get word of it's existence out there, and the second comes "because people don't always know what they want, and you can set them up with the right product for them, because you know more about the available products than they do" (he sells power tools). I'm not sure I believe it, but take that for what it's worth.
Also to note: it's apparently very hard to find a decent job in marketing. Without many years of experience, companies will never really trust you to do any of the "cool" stuff that would require you to keep an eye on trends and make major decisions... so they tend to take marketing majors and turn them into salesmen. This means, of course, a lot of traveling and talking to strangers. With my brother, for instance, his company could have just said "ok... we want you to up and move to [some random city across the country], and work there for a while," and he would have had to just leave behind the friends he had made and go to do it. imo, that kind of sucks... but that's where he ended up when he tried to go into marketing, just to warn you.