I know it depends, but ill select a few categories

Racing
RPG
Shoot Em Up
Online Gaming
etc.. etc.. etc.....

Cheers

Racing - Not into racing games much.
RPG - My favourite genre. Any game from The Forgotten Realms series I will most likely like. But, there's three in particular. The Baldur's Gate series, Neverwinter Nights Series (only 1st and expansions, haven't tried NWN2 yet) and unrelated to TFR; Star Wars: Knights of the Old Republic.

Shoot 'Em Up - I prefer FPS Shoot 'Em Ups. My fave is the Deus Ex series. Period.
Online Gaming - Varies. I play RuneScape and I like it not for shit graphics but for it's incredibly vast gameplay, I'm also playing Dungeon Runners, just started but sweet game so far.

That's just choosing from your list. My overall favourite game (at the moment) is a tie between Neverwinter Nights 1 (and expansions) and Deus Ex 1.

for Online gaming.. i really enjoy bf2142 tbh

Racing : Burnout series

RPG : Can't stand them

Shoot em up : The game I've played the most with friends is the Timesplitters series, so much fun, so underrated too. Red Faction is another great series, can't get enough of COD4 either. I prefer much faster game play games that are not too sci-fi, much more realistic (for example I really do not like Halo).

Online : Battlefield 2 on Xbox Live, wasted far too many hours on this one!

Racing : Burnout series

RPG : OBLIVION (soon to be fallout3)

Sports : SKATE

Shoot em up : HALF-LIFE SERIES ,HALO3, COD4 or GEARS OF WARS or Crysis (i can't decide!)

Online : Warrock

Ah, the Time Splitters series. Such a sweet game. For console games, my fave would have to be Dynasty Warriors/Samarai Warriors and the Devil May Cry series.

Racing: Mario Kart 64
RPG: Final Fantasy 3 US
Shoot Em Up: Golden Eye
Online Gaming: Starcraft
PC: CIV4

Racing - I've never gotten into them... I think the last one I played really was Crash Team Racing (yes, that long ago). If the rumour I heard that GT5 has the Top Gear track is true though...
RPG - I like the original Neverwinter Nights (since it's the one with a Linux client), Diablo II, the Final Fantasy series...
Shoot Em Up - Works by ID Software or Infinity Ward
Tactics & Strategy - Starcraft probably
Platformer - Ratchet, mostly because I want the new one...
Online Gaming - CoD1 rifle only servers.

Im not into gaming that much but I have some favorites.

Racing - Never played any racing game lol
RPG - Elders Scroll 3 for Xbox.
Online Gaming - Team Fortress and Counter Strike are the only ones i ever played online, good games.

and my all time favorite, Metal Gear Solid series.

I'll throw out some good ones for you, and some more categories.

Racing: I used to like the grand turismo series...but I don't like racing games that much

RPG: Final Fantasy VII (also by far the best video game ever made)

First-Person Shooter: hmmm... Doom? haha.

Tactical Shooter/Online Game: Ghost Recon, I'm not talking about the advanced warfighter series (which are amazing) but the first one! Awesome game. Halo 3, is also incredible, but in my opinion it doesn't match GR.

Fighting games: Mortal Kombat I & II...hell yes! Then comes Super Smash Bros. on the N64

Sports: In my opinion...the worst video games out there.

misc./rhythm games: Guitar Hero!! It's addictive, but also slightly pitiful since i'm a real guitar player.

Racing: Definitely the Gran Turismo series.

First Person Shooter: I quite enjoyed Black, but don't really play many FPS games.

Miscellaneous: Guitar Hero series since they are the only games that I have played off and on for the past year.

MMORPG: World of Warcraft: The Burning Crusade.
As for all the other catagories, screw 'em...hehe.

Aye. Keep the classics alive.


Online Gaming: Supreme Commander/World in Conflict

Racing: Burnout: Paradise

RPG: WoW?

First-Person Shooter: Call of Duty 4: Modern Warfare

Tactical Shooter/Online Game: Warhawk

Fighting games: Tekken

Sports: Wii Tennis?!?!?!!?

misc./rhythm games: DancE DancE RevolutioN!

I have read a lot about Warhawk...
Is it fun, and what exactly is the game play about?

Racing: Need for Speed Underground and the newer versions.
RPG: I don't play those.
Shoot Em Up: America's Army, COD4, First To Fight, etc. I'm a huge military gamer.
Online Gaming: America's Army and COD4.

Gasp!

MX vs. ATV Unleashed..can't wait for the new one coming out

Racing: Project Gotham Racing
RPG: Blue Dragon occasionally, though they aren't my cup of tea
Shooting: Any of the Battlefield games, Halo
Strategy: Any war related one, though Sudden Strike is my favourite, plus the 3rd one has just been released after years of development.
Online: BF Vietnam seeing as it runs best on my PC and is the best in the series

Racing: certantly burnout
RPG: i dont realy know hard one there are lots of good ones
Shoot Em Up: halo (singleplayer)
Online Gaming: bf2142

What is that?

by bf2142 he means Battlefield 2142: http://en.wikipedia.org/wiki/Battlefield_2142