Lol, you can't just give the polar extremes and say that those are the best two options. An up to date PC has the best specs, but is undoubtedly the most expensive. A Wii is definitely least expensive console, but is also the weakest console, by a considerable margin (anyone see Spiderman or Harry Potter on Wii???). That doesn't mean the Wii doesn't have advantages in other places, but that is not the issue. The PS3 or the 360 are somewhere in between, and are good options for a lot of people. First party publishers are able to do some pretty phenomenal things as well since they often build their own engines, their own tools, and do not rely on stuff like DX 10 (which is fantastic), but it limits the game in some ways because it is not hand-made for that game.
In any case, every console/computer can do something better than the others, so the point is somewhat moot.
This is really what I was (indirectly) getting at, Akuma, although the last line is something I think you disproved yourself.
What does the PS3 do best? I'm really interested to know that. It's not the cheapest, it doesn't have the best graphics, it doesn't have the largest library of games, and its controls are neither the most customizable nor the most precise. It doesn't do anything best.
But I will tell you what it does do: it gives a great middle ground for some people (the ones you mentioned above, who don't want to spend too much money, but will spend a good deal, and who don't care too much about graphics, but care somewhat) and most importantly, it has games you can only play on that platform. If you personally like those specific games, then the PS3 is the best system for you.
I was being deliberately obtuse to prove a point, Akuma. People try to discredit the Wii and PC at times by saying "It's too expensive," or "The graphics aren't good enough," or so forth. The problem is that every one of those arguments can be thrown back in the PS3's face. The PC has better graphics than the PS3, it has more precise controls, the Wii has a larger game library, and it is cheaper. Instead of arguing that the PS3 is the best of the best, simply argue that this specific system is the best system to meet your specific needs. Which is totally cool, by the way! I just am tired of people trying to make the arguments I've listed above.