I do use the recommendations, but I don't bother with a lot of the adjunctive features; I found they were redundant and mostly just suggested books already offered or ones I already owned. The anti-recommendations seemed split between ones I do already own and ones I'd never bother buying ever.
I find I get a lot of recommendations either from my friends list or member suggestions. I stalk my friends' recently added lists and get a lot of ideas from that. I've been known to email them to ask where they found certain unusual items (though the answers are usually something along the lines of "I was on vacation in this tiny village outside of Munich and I found this little shop in someone's back closet where they had a single copy of this volume, and incidentally the retail price was 100 euros" which tends to be disheartening). I mean, if with my weird tastes I think something's actually obscure and unusual, it's probably truly obscure and unusual, not just a mass market paperback I somehow missed in the NYT best seller list. It's a lot of fun doing this and it's an always-changing recommendation list I love. My LT friends have eclectic interests and tastes, and there's always something fascinating and promising among what they're newly cataloguing or reviewing.
I did get some ideas from the built-in LT recommendation lists, but since they're pretty static, it was more of a one time shot. Mostly what I found were volumes I'd already heard of but hadn't thought of for a while, but which I moved to my BookMooch wishlist (which functions as a TBR/to buy one day list for me as well as a Mooch list). It was classics, both among adult and children's literature for the most part, which I enjoyed seeing as recommendations, but there was very little new or surprising. Still, I really appreciate the feature and do check it periodically.