Any warnings what to avoid?
NX2. ;-) I'm half joking there. Lightroom is good enough for me. I like the keywording in LR2, but it's definitely got room for improvement. I'm looking forward to (this is my euphemism for procrastination) the day when adobe adds face recognition to a future release of lightroom. Have you ever played around with picasa? It's free and it does face recognition and the keywording is not too shabby. Using their face recognition, I've found images of my kids that I forgot I took. I hope LR3 will implement it so I'll be able to port my LR2 database there with my keywords intact and have it automatically tag all the face-containing images that I've missed keywording.
edit: I forgot to mention the metadata browser in lightroom, which is absolutely great to use.