I couldn't call any of his films "excellent", but he has done some decent, if flawed, watchable flicks.
Now I think about it, probably only
Panic Room and
Fight Club* are truly crap.
The Game was extremely boring too, but quite well made. Even his dreary remake of
...Dragon Tattoo had some moments.
I must catch up with
The Social Network and
...Benjamin Button though.
* Once again, sorry! I think it's rubbish!