There is such a thing as a bad lofted bed. I experienced this as a kid when I got the chance to pick out bedroom furniture for the first time. I chose, of course, the coolest bed ever: It had a desk and a bookshelf underneath it, and I got to pretend I was sleeping in a tree house. Only problem was, we picked it up from the furniture store in a flat box...and the only directions included were in Russian. After one failed attempt to return it, a lot of cursing, hammering and some crying, I had my loft bed, and it was actually assembled in my bedroom.
However, there are good loft beds out there that you won't have to agonize over foreign directions to get. In fact, it seems like lofts have gotten even cooler since I was 12. For example:
Photo Credit: Tumidei
If your house is short on space, lofting can be a great way to maximize the area you have to work with. Go up, and get organized!