Like I said, when you define the criteria solely to the 360's strengths the decision looks easy. Of course that just shows your bias. You could easily start looking at other criteria where the 360 is weaker.
Are you interested in HD movies?
Are you concerned with the sound of your media components?
Are you concerned with reliability?
Are you going to play online? Do you mind additional cost?
Do you game on a PC too?
The criteria I was defining was for the masses, those that don't fall into specific bins. They just want to play. Some people don't want a swiss army knife for a console, they just want to play games. For those people if you look at it objectively it's an extremely easy choice. When my adorable niece asks me what to get, she falls into that category. She wants a box that plugs into a tv that plays games. It's impossible for me to recommend anything other than a 360 for that today, which is what I suggested she get. (Mind you, her immense adorableness prompted me to just go buy her one later that same day). Now if she said in her squeaky voice "I want Little Big Planet", then I'd have bought her a PS3. But she didn't, because she is one of the millions that asks that time honored generic question of "I want to play games, what do I buy?". Very easy answer to that today.
That's why I also mention demos because they are part of just playing games. I skip all the above points you mention because those fall into the more subjective realm. For example take your "Are you interested in HD movies?" line. If someone really wants HD movies on optical disc, then they will and/or have already gone PS3. If they want HD movies streamed then they will and/or have gone 360. There is no clear cut choice there, it's subjective. I'm not into streaming, I want the optical disc so for me it's PS3 for hd movies. For many of my friends they have no interest in having discs anymore, so they only stream, I see them on Netflix on my friends list every night. Subjective, so I skip it.
Same with your "Are you concerned with reliability?" statement. There is no proof to suggest that the current builds of either machine are different in reliability. What is different though is warranty. My 360 got fixed free, my PS3 required a $150 fee when the bluray drive died. Which is better, free repair or paid repair? But I skipped that because again it would lead to a million subjective posts from people that still believe the 360 has a 127% failure rate while the PS3 actually hatches new PS3's over time.
Or I can take -tkf-'s "cheap harddrive upgrade to support it" comment and make it subjective as well. I *hate* the PS3 setup for the harddrive, it is horrible for me. Can you upgrade it? Sure. Can I pop it off and bring it to my upstairs 360, friends house 360, family members 360, etc? No! It's screwed in there permanently making it a pain in the ass to bring my downloaded games, saves, etc everywhere with me. When I have family sleeping over I pop the hdd off the downstairs 360 and pop it on the one in my bedroom, and I can play everything there. Same with going to a friends place. I could argue that the easily removable nature of the 360 hdd makes it 10x better than the PS3's setup. But I didn't in my initial post, again because it's subjective. For some people having a 500gb hdd fused into the machine is what is most important. For others it's transportability.
Etc, etc, etc. I could counter argue all the subjective points mentioned, like that the PS3 supposedly has better and more varied exclusives (certainly not even close to true in my book) but I'll skip it. What is not subjective is the multi plat games. Multi plats are better on 360, attach rates are high, most purchases are multi plat games, therefore you can get better versions of the same games on the cheaper box. That is not subjective because we are talking about the same games. Now I could have initially made it subjective by stating why I feel multi plats will forever be better on 360 for a variety of tech reasons. But I skipped that figuring it's still subjective, I'll just stick with the basics, the games.