Here's something I never thought of before. We're all aware of the possibility of kids being called by their first name and last initial (Isabella M., for example) when there are more than one in a class, or anywhere else for that matter. However, there is another possibility I didn't think of before - they could turn into "the ugly Isabella," or "the weird Isabella," etc. Granted, they could be known as "the pretty Isabella," or "the Isabella that saved fish from being eaten by the science teacher's octopus that climbed out of its tank," but I'm just letting everyone know that it could happen. Just one more reason to advocate rare names. This happens most often in school, where there are a bunch of kids from the same generation packed together, but I did mention that it happens other places as well. In school I was Cristina S., while as an adult people have to find other ways to refer to me, given that I am competing with other Christina's and Krystyna's from my generation. This might not bug most people, and I don't mind too much myself, but I don't want it for my child. I'd like them to have a rare name, not having to compete with kids with names in the top 10, 100, or even 1000.
Also, just found this book - The Everything Baby Names Book (2nd edition) by June Rifkin, 2006. I really enjoyed it and recommend it.