Well... as a CS5.1 user, Adobe Bridge user, and long time owner of Lightroom 3.0 (and earlier) but non-user of LR until recently I would have to say that if given the choice, I would take Lightroom hands down. I did some Lightroom training on a website called
Lynda.com and I have come to love LR3. I can do almost everything in LR3 that I was doing in Bridge and ACR. I use CS for minor edits or layer masks. The one place that I think Bridge beats LR3 is keywording. I don't like how LR3 keywords. Other than that, it's the bomb