Ditto J-D-jazzy-Dyal. A remake is only bad if it's, well, bad.
Personally, I liked Ocean's Eleven. It was fun and goofy and didn't take itself too seriously, and it was updated nicely for modern security (at least enough to fool someone who didn't know anything about modern security, like me). I also thought Brad Pitt did a really nice job, and I'm not a big Brad Pitt fan all the time.
I actually really enjoyed seeing both versions within a short timespan and comparing them. It was fascinating to see the relative simplicity of the original's plot -- people today are expecting more -- but also the fact that the original had (avoiding spoilers here) a slightly different ending as far as where the money ends up.

Characterwise, it was great to see the Rat Pack completely ignore the demands of the plot in order to pal around for awhile, which seemed to carry through in the remake. The Rat Pack also did a great job of exploring racial issues in a real but not heavy-handed way -- the line "Now, how do you wash this stuff off?" really really worked for me. The modern Ocean's Eleven didn't really address that stuff, although they played off it a bit with Bernie Mac's character and the "Angry Black Man" con, but on the other hand, the modern Ocean's Eleven wasn't radically misogynistic, either, whereas in the original, the women are either evil, and recognized as such, or vague doormats.
So I at least liked both, and liked watching both for different reasons.
On the other hand, the Lucille Ball version of "Auntie Mame" never needed to happen. Ever. Evereverever.
I didn't like the "I Spy" remake with Eddie Murphy and Owen Wilson. I have fond memories of watching reruns of the original with Robert Culp and Bill Cosby -- with a black man getting equal footing and two smart characters trading quips as they handle the secret agent shtick -- and seeing it dumbed down with Wilson and Murphy really ticked me off. If they're going to do a remake that has so little to do with the original, why not call it something else? Or call it something that I personally don't care about

? The recent "I Spy" movie could just as easily have been called "Spies Like Us 2000" and nobody would really have known the difference.