Is there a patch out ??

[Murmandamus]

So then, just since I'm slow

You cannot play the game with an outdated patch #, correct?

If you launch Steam and play while connected to the internet, you're ok? (This is for SP)

Alternatively, I would assume you can't play MP with an outdated patch anymore, correct? I remember the old days of MTW and RTW where we were playing on all different versions #'s.

That's all done? One version basically, as in "working"?

To answer your questions: yes, yes, yes, yes and yes

Usually the only way to avoid a patch of a steam game is to run steam in offline mode. If your online though, it'll install any updates before it'll let you play it.