I got a Wii at launch, but unfortunately — despite a handful of really terrific games — Nintendo's "broader audience" strategy has left me yearning for more "hardcore" games.
I liked the prospect of playing PC games (many of which are 360 ports/dual releases) on my Mac, but a plethora of graphic card issues and Windows Vista issues have left me frustrated and unable to play much of anything.
So to put it simply, I got a 360 because of the games. There are
very few PS3/PSN exclusives that I've any interest in, including upcoming games, while there
are 360 exclusive games that I want. Price played some factor (I don't need the @#$% expensive wireless adapter) but was secondary. And easy connectivity with my Mac for media streaming plus Netflix integration also supported my decision (admittedly I have no idea how well the PS3 functions as a media center). I have zero interest in Blu-ray. I also love the 360's controller, while the Dualshock 3... er I mean Sixaxis

feels dated and, like it's predecessors, uncomfortable in my hands.
I'll also say that I bought a 360 despite my genuine dislike of Microsoft products (their software at least — I've had some mice of theirs that were really quite nice) and all the RRoD units. I was reluctant at first, but feel very comfortable with my choice. Before any of the three consoles came out I might have been leaning towards the PS3, but the tides have shifted.
I have to say, I prefer the PS3's quietness, styling, HDMI & optical audio as standard.
The 360 isn't any louder than my PS2 (original "fat" launch unit) or Wii. Which is to say, not totally silent but pretty quiet. If you get the Elite it comes with HDMI and optical audio as standard (even if it wasn't available at first).