Strangely enough I've gotten this error only once, and I restarted Steam, didn't work I'm going to try to restart my computer right now. Edit: Scratch that, that didn't work either. For some reason this only started happening out of the blue, and it only affects Empires, all my other games on Steam work.
I think it has something to do with AA 3 being released ( and failing) today. Steam is one of the official distributors of AA3, and the best one since deploy program sucks. All teh little kids want to play it so they all try to unpack their files as soon as its released, but they need to connect to steam servers.
Ah, Americas Army, that game.. is the only in which I can actually meet some people who are in the military, now that I think about maybe EvilEd should go on there, all members of the armed forces get special insignias next to their names, but thanks for the info Hamster. Edit: Great, now the majority of the games don't work.