Ask people how they feel about Dilbert. If they work in an office environment, chances are they love it. If not, chances are they'll say it's poorly drawn and unfunny. Let it be said that, unless you're an avid Slashdot reader or have a burning passion for Linux, you'll feel the same way about the comic strip User Friendly.
If you are a part of that culture, though, you will no doubt find many strips you'll want to photocopy and stick up on your walls. Not all of the jokes fly, but you will love the few that do, primarily because you can relate to them.
Some of the jokes are dated, and considering that many of the events referenced are not necessarily earth-shattering events, it would have been nice to have footnotes or an appendix with references. One joke shows everyone missing from the office on May 19, with the lone character asking if today is a public holiday. Some hard thinking might remind you that that was the day "Star Wars: Episode 1" was released to theaters. Years from now, no one will be able to understand this strip without some historial context.
Of course, the main reason I bought this book was for the cool cover design. As a proud owner of several O'Reilly "animal" books (I will buy no other computer manuals), I just had to have this one as well.