I use linux and maybe I could help.
1. Wine for Linux is just a joke. You have to go through a lot of hassle to get any Windows games to work, so wine is not at all an option. Better to depend only on the Native games.
2. There are almost 200+ games on steam for Linux, so if you are a new gamer, then you might find just enough games for you. Linux is a good gaming platform for someone who loves games like Indie games. Games like FEZ, Trine 2, Mark of Ninja etc work just awesome on Linux.
3. If you are looking for FPS games on Linux, then you would be disappointed. There is not a whole lot of FPS games here. Forgive me for saying this but FPS games on Linux like Cube 2, etc look like they are from the early 90's. So, it clearly does not even feel like FPS games.
4. If you like games made by Valve, then Linux is a great platform, because of the awesome support form Valve. There is Team Fortress 2, Left4Dead 2, Half Life, Counter Strike, and new games coming from Valve everytime. So, if you are like Valve's games then you would like the Linux as gaming platform.
5. There are some big titles here like Serious SAM 3 BFE which looks fantastic but there are way too much killing and the end experience is that it is not that enjoyable game.
6. Also there are reports coming that Crytek (the guys behind the Far Cry and Crysis series) that they are porting their Crytek engine to the Linux platform in sometime soon. Also Metro Last Light is soon coming to Linux as announced by the company behind that game.
Conclusion :
If you are looking for a new platform for gaming and like the Indie games like FEZ, Mark Of Ninja, etc. Then there are titles that you might like. But if you are looking for some FPS gaming, then the Linux is not prepeared yet for that.
Yes, with the steam OS coming, there would be a lot more games coming to Linux. Infact games are coming to Linux now faster than ever. So if you are someone who wants to support the Linux gaming Community, then feel free to join us. We would be delighted by new guys coming to Linux.
Also with Steam OS right around the corner. There would be releases for the Linux. So, just stay tuned. Finally the era for Linux gaming had arrived.
You can have a look at all the games available on Steam on Linux here at store.steampowered.com/browse/linux/ . The library would eventually have some big AAA titles, thanks to Valve's vision. If you can join the Linux gaming community, then we would be delighted by a new member joining out community.
I hope this helped.