Look at the people with smiling faces in the above illustration. It's not too difficult to figure out what's going on: it's their birthday, and they're all happy because they're about to get presents. What if they knew that you had totally spaced on the fact that they were celebrating the anniversary of their birth? Fortunately, there are plenty of services that will remind you of friends' and family members' DOBs, and Amazon is now joining their ranks with a Facebook-integrated program c