Y'all ready for this?

Last time Valve did an ARG ("alternate reality game", in which they drop clues all over the place and you have to decipher them to find the hidden message), Portal 2 was announced. And, granted, Valve had been doing a lot of polishing and re-tweaking on their games since then, but hadn't announced anything new.

Well, I got good news, bad news and awesome news.

The good news? They were working on something, the sneaky buggers.

The bad news? It's not Half-Life 3 (at least, not that we know of), although the emerging pattern suggests they won't confirm HL3 until a couple of days before they release it.

The awesome news? What they're releasing tomorrow looks amazingly fun.

Mann Vs Machine (and if you're not familiar with TF2 lore, there's a reason it's "Mann" instead of "Man") is a new co-op horde mode for TF2 that has both Red and Blue fights off hordes of killer robots. Right now we only know little tidbits of info about it, as well as the video here, but it's fixin' to be the new staple of co-op, just like TF2 managed to become the poster boy for team-based shooters. And it's most probably going to be just as free as TF2.

Well done, Valve!