I think this is an adorable idea and would go a long way towards retaining users. It should be attached to the cake icon though: if you have that option checked, viola, goodies.

I like the birthday list idea, would love to send random people a present :)
I don't know about this idea.. I really don't like my birthday as is. I rather just keep the icon of that cake next to my username then a big celebration from Subeta seems too much work
I think something like a cake item or maybe a random present (out of a subset of items?) would be cool. To all the people who hate their birthdays -- that's something you're going to have to look at in real life to change (make new friends? I can sort of understand the feeling, but you CAN live a life in which you enjoy your birthday once a year, haha). I think for all the people who don't like their birthday, there are plenty more who would appreciate a tiny gift on a website they frequent. :)
I don't see why a small "Happy Birthday" in our sidebars and a slice of cake would be such a big deal. A list of birthdays on the news page would be nice too and maybe for those that don't like their birthday, there be an option to turn it off? You can already turn the cake icon off so why not the whole entirety?
