On the one hand I like the idea of DLC for games that are enjoyable without DLC. If I feel like I got my money's worth from buying the game by itself, then DLC is a safeish bet and a good deal for me to continue playing the same game.
That said, I really didn't like Fable 3 and got the DLC because I didn't know what else to do with my xbox points. Also felt the DLC was lame though at least in line with how lame the rest of the game was.
In ME2 the DLC didn't really impress me. The reason being that I felt running around doing errands for random people wasn't in the best interest of the galaxy anyways and I also disliked the combat. ME3's combat for me is fun on a lot of different levels. I can't even tell you what differences they made to it, but for some reason I like the combat in ME3 whereas I didn't in ME2. The DLC in ME2 was combat heavy and because of that I didn't really enjoy those missions.
However, when DLC stuff from ME2 started coming up in ME3 I was pleasantly surprised. Too bad
Zaeed might never leave the Citadel if they don't give us some awesome DLC missions that go over the Reaper's attack.