Grindr's most popular city is London, with 350,000 users, and the speculation is that the arrival of thousands of athletes caused the system to overload. However, not all Olympians are gay. In fact, I would argue that very few of them are....maybe 7-10% if you take the usual statistical model. It's possible it was just a busy sexy summer weekend in London and it crashed, just as the athletes happened to show up. Friends in NYC w/iPhones report that Grindr crashes/freezes are becoming more common as the service grows more popular.
Anyway, it does make for a good headline though....and it has been racing around the internet today because of it.