This has been popular cult (or cultishly popular?) favourite for years, and having finally caught it I can see why. Like Dilbert it appeals to anyone who's ever been a cubicle cog in a corporate machine. The film starts off really strong - deftly sketching the main characters over the opening credits. The run on the "TPS reports" worked really well too, especially the clincher in the restaurant. The momentum isn't quite sustained for the entire movie, but enough jokes land that it's still a satisfying viewing experience.
On a tangent: Not a big Friends watcher, but have decided that of the six stars only Lisa Kudrow and Jennifer Aniston have demonstrated their acting credentials outside the TV show.