I own both of these systems, the 360 gets a majority of my gaming money. Mostly because it just works a little better.
They're both great devices, but my 360 boots up faster, the controller works better through walls (this is silly sounding, but I use Wireless HDMI a good bit these days for gaming in other rooms), the controller is superior imo, and most games I'm interested in are multi-platform. The PS3 these days feels like work, it takes longer to download and install updates, the whole installing games thing is a pain in the ass, and the controller is uncomfortable and awkward to use (who decided two analog sticks should go right next to each other?). It's also a first-gen PS3 (60gb), and the thing is about as loud as the first gen 360s -- doesn't really bother me, but worth noting. In terms of exclusives they both have their pros and cons, I greatly enjoyed Gears of War and I think Uncharted may be my favorite franchise of this generation. Beyond that, I'm burnt out on Halo, and Fable never hit its potential. Resistance and Killzone were dull, and Infamous reminded me that I'm not much of a Open World fan. I'll be the only one but I preferred the Splosion Man series to LittleBigPlanet (and was disappointed it wasn't the continuation of Little Big Adventure).
This generation had no identity, multi-platform everything (which makes sense considering the cost of development) but the game consoles are damn near interchangeable now. It all comes down to controller preference and some minor graphical differences.
And yeah, a higher attach rate for the 360 in Japan would make sense when there's so few of them out there. A lot easier to make sure those 10 people have 10 games than making sure a million people each have 10. And hilarious theory/thread regardless.
