I'm not a fan. Especially since they added the "make a donation to XXX for friend's birthday" option. I think it was last year when I started noticing those. On my birthday, facebook oh, so graciously directed me to choose a cause for my friends to donate to. I declined. But I think that's when I became dispirited with the facebook birthday reminders. It all just felt forced and fake.
So I decided I wasn't going do birthday well wishes over facebook anymore. Of course, I send some sort of Birthday Greeting to my nearest and dearest. I either know those birthdays off the top of my head, or at least have them written down in that section of my address book.
In the spirit of fair play, I also took my birthday information out of my profile. You would be right if you guessed that I did not receive a single birthday greeting over facebook this year. My nearest and dearest managed to get to me via other means.
I get that a quick little greeting that could brighten someone's day can be a good thing. I get that some people keep track (cough, cough YDN). For me, it's one more thing not to like about facebook.