Used LauncherPro, GO launcher and ADW. I liked GO until it went wonky in landscape. Presently using LauncherPro. As stated above it really comes down to personal preference.
I have been using zeam launcher. It is very light weight, with just enough customizations that your head isn't spinning. I have used all other launchers (including spb shell 3d), and I always find myself going back to zeam.