That's some bullshit, and it needs to stop.
There's no litmus test for being a geek, much less a full-blown certification. You don't have to earn a merit badge to be a geek, and you sure as hell don't have to get your application approved by the Grand Council of Geekdom. There's just one real requirement: a passion for one or more of the things we call geek. That's it. That's all.
I know that for a lot of us, being a geek is more than that. It's a way of life. That's fine. Totally cool. It doesn't, however, give you the right to judge "lesser" geeks unworthy of the name. It's not a tenured position, either. Just because the guy enthusing about the X-Men in your favorite comic-book store learned about them from the movies and has only read comics for a year (or a month, or a week, or a day) doesn't make your love for Professor Xavier's band of misfit mutants any more pure, or real, or meaningful than his. The fact that you got beat up for reading the comics while that guy was playing some kind of sports ball doesn't mean shit, either. Not when it comes to fandom. His enthusiasm and passion for it is no less real, or valid, than yours.
This attitude is especially onerous because its most common target is women. The thought process goes something like this: Women didn't use to like geeky stuff, so if a woman likes it now, they must be faking it for some reason, like to get the attention of a guy.
Uh, no. Just no.
First off, plenty of women have always liked geeky stuff, and just because you didn't know any girls who played video games when you were growing up doesn't mean they weren't out there. Second, it's self-defeating. It's true that there are a lot more male geeks than female, but part of that has to be the hostility that women encounter when they show up to a gaming shop to play some Magic, only to be met with sneers of derision and insulting questions like, "What, did your boyfriend teach you how to play?" In other words, there are never going to be more geek girls if you fucking trolls don't stop chasing them off. Finally, faking an interest in geek stuff to meet guys ... really? Do any of you really believe that? There are easier ways to meet dudes, especially dudes who by reputation have a hard time meeting women, than by diving into something as deep and esoteric as, say, Dr. Who fandom. It'd be easier, and less likely to come with negative social baggage, to fake an interest in football -- and you get to drink while you pretend to enjoy the games.
Now to some degree, this trend is understandable. Many of us grew up when this stuff was beyond uncool, being ridiculed, shamed and even assaulted for the sin of carrying around a shitload of polyhedral dice, graph paper and rule books. Now it's on the verge of mainstream acceptance and all of a sudden we're seeing an influx of clueless noobs -- or worse, people who liked it back in the day but weren't willing to admit it. It makes us protective, possessive even.
Understandable, but stupid.
The boom in geek culture has been a boon for all of us, and more people just means more money for the creators, more chance of kick-ass movies, books and TV shows being made, and maybe someday a widespread cultural appreciation for cosplay and tabletop gaming (hey, a guy can dream, right?). These are good things. We never would have gotten those lavish, stupendously expensive and lovingly accurate Lord of the Rings movies if geek culture hadn't become mainstreamed. We wouldn't have 25 decent-to-great science fiction, fantasy and horror shows on TV to choose from. And no one would be paying me to write about this stuff, that's for damn sure.
So the next time you want to dismiss some geeky-come-lately for not being as pure nerd as you, just stop. Welcome them to the clan. Offer to loan them some books, or that rare import DVD you tracked down a few years back. Show them some other cool stuff that's like whatever brought them into the fold. Even better, if you see some mouth-breathing bridge troll shitting on a noob, intervene and chase him off (it's pretty much always a dude). Geekdom will be better off with more of the new guys (and girls) who aren't walking stereotypes, and less of the people who make everyone think we're all clueless, hopeless antisocial losers.