Now I love video games as much as the next geek and I've always assumed it was a light hearted hint towards company culture rather than a hard requirement.
But I just find something a little off about stuff like this, like it sets off a little red light in my brain that I can't put my finger on.
We would probably think it was weird if they said "we all love cricket so you should too!", I guess it feels a little patronising to be told "of course you love Xbox, you are a geek after all!"
As a Segue the use of the term "geek" in job descriptions irks me also.
Edit: Wording corrected
Segway: a goofy 2 wheeled scooter invented by Dean Kamen.
Segue: to make a transition from one thing to another smoothly and without interruption: The conversation segued from travel anecdotes to food.
These are probably the same places that think adding an extra hour to your work increases your productivity by 16%.
What raises the red flag is making it such a prominent part of the actual job description.
It's simply one more avenue of lead generation for recruitment. And a very creative one that's likely to get them quite a bit of exposure. It also has the benefit of clearly demonstrating that they are a "fun" company, not your run-of-the-mill boring enterprise product corporation.
As with all the other "hiring games" that Google and others do, you can also just submit your resume, you don't have to play.
Personally, I like working with other developers who like games and good beer. I haven't had great experiences with the type who lock themselves in their offices and don't come to happy hour.