My Worst (in no particular order):
1. Crossroads of Twilight by Robert Jordan - Wins the 'Most Useless Book in a Series Award,' in that it really didn't further the plot at all. In fact, the first HALF of the book is spent retreading the last day and a half (about) of tha last book. When a whole chapter is used to describe a woman taking a bath without giving any nice, juvenile, sexual descriptions, then the book has more than jumped the shark, it jumped eight sharks and killed Hitler with a garbanzo bean.
2. Redemption of Athalus by David Eddings - I like Eddings despite his problems. His villains are worthless, his heroes perfect, and the plots simplistic, but he usually writes some good, fun stories. Not so with Redemption of Athalus which manages to make villains even more worthless than usual who are getting the crap kicked out of them by a bunch of cardboard, super heroes. Flush it, it sucks.
3. A Sword of Truth books by Terry Goodkind - Poor characterization, poor writing, boring, poor plot, pretty much poor everything.
Most Overrated Books:
1. Dune by Frank Herbert - Yeah, I can see how everyone and their dog loves this book, but it honestly didn't do a damn thing for me. I've tried to read it at least twice, but I usually only get about halfway through before I get bored and put it down for something else.
2. Deadhouse Gates by Steven Erikson - A pretty good book actually, with some fairly solid writing and characterization, but it's overly philosophical and Erikson REALLY tries to write in a poetic, prosaic style that occasionally hits the mark, but usually ends up falling flat or sounding very awkward and very stilted.
3. The Dark Tower books by Stephen King - Great ideas contained herein, although marred with usually poor execution. Let me say that, overall, I am not a King fan. His dialogue usually sounds stilted, he's very verbose when brevity would work better, and he seems to really stray off on tangents. The Dark Tower suffers occasionally from this, but really, the biggest problems I have with these books is that the characters do very little for me (aside from Roland, I dislike the rest) and the fact that the series seems VERY aimless at points, as if King had no idea of what was going to happen beyond the next few pages.