My background: My first home console was a Telstar "Pong" system, and I have gone on to own just about every major console released in the US and one import (Super Famicom). So I'm an old school gamer who currently works as an artist/designer for a major publisher (and a couple of smaller ones as well). I got into game design in college and published my first title shortly after graduating. Since then (over a decade), I've gone on to work on countless number one and top ten hits, etc on all the major platforms. If you are a gamer, there is a good 75% chance you've played several games I've worked on since I've done games for most of the modern platforms (PS1, PS2, PS3, PSP, GameCube, Wii, Xbox, X360, GBA, NDS, PSP, PC, Mac).
When it come to the 360 vs PS3 debate, for me, it's a no brainer. If you can only buy one (both is better, but not always financially feasible) I suggest picking the 360, it is honestly my favorite console of all time. The big reason I can see picking up a PS3 over a 360 is if you plan on watching a lot of BR movies, but only play the occasional game. To me, it's games first, then added extra features. The 360 has the games I want to play, and the features that make gaming enjoyable (online, system wide custom soundtracks, no installs). Not only does the 360 have more titles, it has more AA and AAA quality titles than the PS3 and Wii combined. That isn't to say the PS3 sucks, or doesn't have any good games (it does), but it has far fewer titles, not as robust online service, and still lacks many of the features that the 360 had on its launch day. The PS3 only recently (some three years after the 360) officially announced that it is about to get in-game XMB (although no details have been released publicly).
When it comes to development, I think most people have heard the stories. The PS3 is harder to work on, even now. While new architecture is always a pain to learn, the biggest issue is the tools. It's so much easier to make games on the 360 since MS understands software development and provides the tools that make it work seamlessly. Without going into detail or specifics, as a consumer, if you look at the retail operating systems you can get an idea of how the different the two sets of development tools are. Since the 360 OS takes care of things like the online features, custom soundtracks, scaling, etc, the developer doesn't have to waste time and resources creating it themselves each time they make a new game. Sometimes it's just little stuff, but that little junk will add up to a few weeks worth of extra development time (for a platform that will have the lowest comparative sales). Since the PS3 games take longer, but deadlines are often set in stone, PS3 titles generally are less polished than 360 titles.
The Wii - Great comeback for Nintendo. It's a fun little system that has a cheap price and wide appeal. It is THE system to own if you like having people over to play games or live in a community setting (dorm, retirement home). That said, it personally doesn't appeal to me as a primary console. After playing Zelda it became a dust collector for months and only saw the light of day occasionally when people are over and we'd play Wii Sports. My 360 gets the lions share of game time by a few miles.
I personally can't see owning a PS3 or a Wii as a primary console since the AA & AAA titles are few and far between. If you are the type of person who at the end of a consoles life, only owns a half dozen games, then the PS3 and Wii won't seem under supported. But if you are like me play and like a wide variety of games, the 360 might be your best choice.
