Team Fortress 2 reaches new player count record at 250k players

I've always wondered if there was some weirdness going on with the player numbers. It felt like its been doing really well number-wise the past couple years despite being (relatively) abandoned by valve.

I remember seeing some people talk about that on the subreddit, but I don't know what conclusion people arrived at. Are bots inflating that or is tf2 still really popular?