Currenty I am leaning on the PS3, mainly because the Playstations have been my choice of consoles since the original PS.
The games on Playstation have appealed on me, and I've been fully satisfied with the franchises on Playstation consoles, or maybe I've just grown to like the Metal Gears, Gran Turismos, Final Fantasies, Silent Hills, Jak & Daxters, Ratchet & Clanks, GTA's....
Also the PS consoles have been home to the most original and innovative games (Katamari Damacy, Eye Toy, SingStar, ICO, SotC...) making a widest selection of games to choose from. There has always been a top quality game in any genre, I've never felt the need to buy another console because I thought I might miss some great experience inside a genre. For example, I was tempted to buy a N64 when I had my PS because of Mario 64, and I did buy the N64 just because of that game and then it was worth every penny. PS really didin't have anything comparable at that time.
But ever since after that, there really hasn't been such a game on another platform that had made me go buy that console because I needed to get a "fix" of that type of game.
Now, to the threads' question. What would make me abandon my Playstation preference?
Would I buy an xbox360? Not likely.
Although currently it is a little tempting, the prime and only reason being Oblivion and the fact that the Playstation brand at the moment does not have comparable visual and technological quality to offer.
I can resist this temptation though, because soon there'll be Dragon Quest released in Eu for PS2, and that'll fix my large scale RPG'ing need for some months. After that the PS3 will be released and AFAIK the Oblivion is also coming to the PS3, so I might as well get it then. PS3 might not have the Oblivion or similar experience at launch though, but again a current gen game, FFXII, will be there for my rpg lusting.
Would I buy Revolution? Impossible to tell at the moment.
There really isn't enough revealed of the Revolution so I could decide now.
The controller is interesting, and I'm sure there will be games I'd like very much.
Would I buy a second console, it would be Revolution because it would offer a different enough experience from PS3 and xbox360.
The prime reason why I might not buy the Rev is that I really wouldn't have time for two consoles and their games.
So, in summary. The reasons:
¤ If my preferred console was delayed a ridiculous amount of time, and I would not have games that meet my qualities to play on my current console while waiting, I would buy what I'd feel would carry me over . But I'd still buy my original preferred console as soon as it'd be available.
¤ If my preferred console would loose two or three of the aforementioned franchises I like to the competing console and I'd know there wouldn't be anything comparable to replace them (say for example, PS would lose Gran Turismo, and I'd know there wouldn't be some other racing games that would be up to the same standard. Losing a franchise would hurt for a while, but after all, it's just a name that's lost)
¤ If my preferred console would lose a significant amount of 3rd party developer support.
¤ If my preferred console had less functionality that I feel I could have use to or would be fun to have (HD movies, Online gaming and other online functions, Media Center type functions, Integration with my other home entertainment...)