Played Mass Effect. Well, tried to. When I first got into some fights in The Witcher, coming off two or three FPSs, I thought combat was kind of goofy, but it was different and it grew on me and turned out to be a lot of fun. Mass Effect is like a third-person shooter, but one I don't find much fun. It's ok, but, just, eh. For comparison, a third-person shooter I had lots of fun with is Lost Planet.
I thought the story would suck me in, but there's just so much dialogue and cutscenes and it gets watered down. Wasn't sure if I was playing a video game or reading a novel. The giant walls of text were just too much.
Does choosing different dialogues do much of anything? In The Witcher, for instance, if you choose early on to let a group of "nice" outcasts steal some supplies and weapons from the people who are supposedly mean to them, later in the game they use those weapons to kill innocents. So the blame is a bit on you. (just one example.) I don't know if your dialogue choices in ME have that kind of effect or not. I was getting the "feeling" not a whole lot you say really matters.
Since the story is supposedly so good, but I was forcing myself to play, I wound up watching someone else's full playthrough video of it. Well, tried to. Still too much dialogue. You walk up to a stranger and they babble off their entire life story. And the SUV scenes looked harder to pilot than that damn hover plane thing in Crysis.
Other people like it. Wasn't for me. So far, the first hour or two of Fallout 3 has been far more entertaining. But, only played the first hour or two.