OK, I'll admit... I enjoyed it.
I still have some reservations, but for the most part the things I mildly disliked are all things that have persisted since Doctor Who restarted in 2005. (Oh, and Stephen Moffat's love of repeated phrases as a device to create fear: kind of getting old, but I'll let it go this one last time.)
Anyway, enough with the minor complaints. If you enjoyed Doctor Who with David Tennant and Christopher Eccleston, you'll probably enjoy Matt Smith just fine. At least in this first episode, I never felt "gee, these two are young." Granted, there's still plenty of time for that to creep in, but we're off to a good start.