I own PS2, PS3, Wii, PSP and DS.
My personal Ranking is PS3>PS2>PSP>DS>Wii.
I will not buy the X360 because I do not like Shooter and Online-Gaming. I would never buy Halo, Gears of War or Fable. I considered buying one for a short time because of exclusive JRPGS like Star Ocean and Tales of Vesperia, but then I decided against it. Some JRPGS have been ported to the PS3 anyway in the meantime.
The PS3 has taken Storytelling to a whole new level for me. Final Fantasy XIII is my best game of this generation and I also liked Heavy Rain, Ratchet & Clank, Uncharted, Little Big Planet, Resident Evil, Metal Gear Solid, Heavy Rain, Katamari Forever, etc. The PS3 offers such a wide variety of genres.
I still put my PS2 on second place because of all Final Fantasy and Kingdom Hearts Games, Ratchet & Clank, Jak & Daxter, etc. Square-Enix, Konami, Capcom and Sony had some of the best Games on the PS2.
The PSP is high on my list because of some strong Square Games. Final Fantasy VII Crisis Core and Kingdom Hearts Birth by Sleep are simply awesome. Watching the Nibelheim incident with PS2-like graphics was one of my best gaming experiences in the last 2 years. I hope there will be a PS3-FF 7 remake in the future....
The DS is also strong, but mainly because of some Square games. That touch screen was something new, but I dislike games that make too much use of it.
The Wii is actually last on my list, and I must admit that I never had a Nintendo console that I played as little as the Wii. Those motion controls took the focus, but after several experiments with "new control schemes" I simply prefer the normal controller setup. I didn't like Eyetoy, I didn't like Sixaxis, I didn't like touchscreen controls and I certainly do not like the Wiimote.
I grew up on Nintendo and totally loved the NES/SNES. But as storytelling and cutscenes progressed, I gradually lost interest with Nintendo. The step from 2d to 3d gaming went bad for me. I did not like Mario 64 and his damn accent was hard to bear. Even Zelda, my dearest gaming franchise at that time, couldn't satisfy me. I got bored after some hours, because after having played FF7 I somehow expected better storytelling.
I will not sell my Wii. I still have a lot of fun with old retro Games from the Virtual Console. But as a whole, the Wii was a big disappointment for me because of the strong focus on motion gaming. I just want games with a great story/setting. Wii Play and Wii Sports grew old so fast that I lost interest after 1-2 hours.
I think the reason why the PS3 is so strong in Europe is because Sony has the support of the Western AND the Japanese Companies. So they can offer a greater variety of Games/Genres.