I'll mainly play TDM and Domination. If War is back, I'll play that quite often, too.
Infinity Ward didn't cater to SnD players at all in MW2. I understand that they were trying to avoid the Score Leaderboard being full of SnD players again, but they went a bit overboard to counter that. When you play SnD, you sacrifice your chance of being high on the Kills Leaderboard, so you should be given a lot of score to compensate for it. If SnD is undoubtedly the best game mode for score and XP again, I'll play it more regularly than I do on MW2.