E-mail addresses and other online handles with a year (or other worthless number) prefixed are very common. Some people seem to think this is due to to a transitory attitude about email, and the internet in general. You see it all the time with e-mail addresses like "firstname.lastname@example.org" or "email@example.com". At first it may seem like people actually seek out these names with the built in expiration date. But, I don't think many people actually try to register as "hotstud99" or "Girly2001". Instead they simply try and register "hotstud" or "girly". But unfortunately, anything you can think of will probably be taken on Yahoo, AOL, or Hotmail (or many other similar services). So then the registration program (in it's infinite wisdom), presents options like "hotstud99". Many people simply take these and live with them (these are mostly the same type of people who believe that "AOL is the internet").
I truly don't think you would see more than a handful of names like that, if it the registration programs were not force-feeding them to people. My own personal rule of thumb is to never ever have a number appended to my username (unless that number has some meaning, like my AIM login of "passportpaige"). In general meaningless numbers and letters appended to your handle show you to be a newbie in many peoples eyes. Scott Adams has done several Dilbert strips on this subject, in one of them Dogbert stuffs someguy in a trashcan for having an email address that is 80 characters long and meaningless.
If you really want an email address or other account for the ages, then you should try and get your first name It is possible, you just have to find a service that is just starting, I managed to get my first name as my email address with a very large service. No one will ever forget such a simple login, plus it lends sort of an air of credibility to you ("Paige" sounds a lot more professional than "Paige3784_1999").