The Android FB app is terrible. Very slow and bloated (up to 13mb now!). There is Friendcaster, which is much smaller and more responsive, though the interface isn't as attractive. I mostly use the mobile site through the Opera browser, but keep the FB app mostly for uploading pics and video.
Apparently, iOS got a brand new redesigned version of the FB app. Hopefully, they will roll something like that out to Android, and not just another version with bandaids slapped on it.