The following thread has good arguments about blitz.
http://www.chessforums.org/chess-articles/8272-blitz-chess-how-help-improve-your-slow-game.html
I have nothing against blitz, but I think that it is a much poorer version, even if fun to play, then the long time control game. The only problem with blitz is addiction and the kind of mindframe it brings with it, so that I have seen people here stating that when playing long games, they don't need more than a few seconds to play "quality moves". Well, even if some of them are reasonable players, this characterizes, IMHO, chess myopia. Chessmasters use the time they have available intelligently. You can watch games in which kasparov, for instance, takes very long on multiple points of the game. But, perhaps, he's just thinking about dinner.
On an analogy to music, I may say that I listen mostly to classical music, but like Iron Maiden, also. Yet, I think that young people that listen to heavy metal only have extremely narrow horizons, in terms of music. Heavy metal may be fun sometimes, but classical music brings a much richer repertoire of musical patterns combinations.
There are some serious studies, on the internet, about the cognitive processes involved in chess. Most of them conclude that fast chess is more linked to simple "rapid pattern recognition". Rapid recognition of patterns helps in long time control games, but long games are about much more than this. I'm not a great player, but I take my conclusion by watching games by professionals, both blitz and long and by some of those studies.
There is a dissertation from a guy named Roring R. on the net, which is very detailed, in terms of statistics, and concludes that fast time controls contribute negatively to a player rating (considered for standard chess). I lost the link to this document and wasn't able to find it again using only the name of the author, but, maybe you should try.
internet blitz chess is a fun entertaining addictive video game. if you want to raise your blitz rating on this website, first do a couple hours of tactics trainer a day. play a computer at around 2000 elo a bunch of times until you are winning a lot. I promise you your blitz rating will jump considerably. but don't think your chess has improved all that much because of this, you're just seeing tactics faster, yours and the opponents. I would say a lot of blitz has to do with your apititude for, liking of video games really, how much you can get into video games. take them seriously etc. I think this is even more of a factor for chess enthusiasts and amateurs than for professionals, but it's still true on that level too.
someone on here wrote that increments drastically changes the nature of blitz, I don't think this is really true. it changes it a little, but not all that much really.