ribbot, don't feel bad. I sometimes think I'm the only person who hates the UG. Which is a shame because I really geek out on the queuing theory. I buy the book from time to time just for the stats geek stuff.
One of the things you need to decide is how you will use your guidebook. We like the organizer feature of the Passporter, for instance. I like making notes in the margin and using the boxes by each attraction to decide if its an A, B or C priority for us. Other people love the touring plans in the UG and the depth of information. Is this a book for dreaming about your next trip and remembering it when its past, or is this a "serious research tool." Will you be carrying it with you (in which case a pocket guide or Birnbaums may be easiest to lug - I find my Passporter to be a "transfer notes and leave it in the room" tool - its too big to carry).
Birnbaums: I like it as a "first guidebook." Its official, so its really not judgemental - don't expect Birnbaums to tell you that Universe of Energy was better before Ellen or Jungle Cruise is hopelessly dated (but still fun). Easy to read, clear maps, pictures. Not overwhemling with information.
Passporter: Part guidebook/part organizer. I really like the new maps (I think they are new). The attraction information isn't as in depth as some of the other books. I like their rating system, which has Jennifer's rating/Dave's rating and a reader rating - you know when something is all nines its as close as it comes to a sure thing, and when it has one eight and a four and a six that maybe you should take your own interests into account before hopping on.
Unofficial Guide: Probably the MOST information in a Disney guidebook, I personally find it overwhelming (especially for first timers) and difficult to use. It has the best and most complete touring plans with the most work done to assure you'll spend the least amount of time in line.