I am incredibly pissed at Steam right now. Civ V for Mac launched at midnight, and since I preordered it I downloaded the files from Aspyr, the company that handled the Mac port, right away. I was able to activate my license in Steam with no issues. But now, despite my having all the files and an activated license, it won't let me install the files (the ones that are already on my hard drive) into Steam because the servers are busy. I was all excited to start playing (and probably play all night and through tomorrow), but now I can't for some stupid reason.
EDIT: I finally got it to work, and proceeded to spend 9 of the last 12 hours playing it. My god, it's fantastic. I've been a huge fan of the series for over a decade now, and this is easily the best one.