Choose the one that have "most" of the games you like.
Don't buy a console just because of "what it can do" buy a console because "what games can it play".
PS3. I don't enjoy the wii really. The control system is annoying over longer stretches of time. I'm sure the ps3 will be dying in a few years too. Console games in general are overrated these days imo.
Your best bet would be to get the PS3 as it has more variety, more anticipated games, and will still have good games being made for it while the Wii has few notable titles and will recieve no new first party which are usually the best games for that system. But if you still wanted the Wii wait for the Wii U in the upcoming year or so and you can play any of those interseting games from the Wii.
Make your decision based on what everything (helpful) has been said here.
Also, take in account your age, the genre of games you play most, who you play with (online/ with freinds) and just generally how much you can spend on video games.
The facts are that ps3 blows the wii out of the water when it comes to power/graphics. The wii has probably the gunnery control scheme and a more lighthearted feel when you play (not to mention 2x as many sales over 360 and ps3). Hope I helped. And if you get ps3, get some of these games (skyrim, fallout, uncharted, dead space, resistance)
PS3.
It has a wider genre of games, & most of them actually play differently, as opposed to the wiis clever tactic of making you tired out or grabs your attention with some random shit to fool you into thinking that your playing a game thats giving you a unique experience.
Beyond that I cant really help you because you didnt ask for anything specific beyond "fun" games, which would vary from person to person.