Considering that I've read the forums here for a while before bothering to post or play, I'd like to make a couple comments...
1. I expect a thorough beating relatively regularly against humans for a while. I got beaten pretty bad by the AI when I first started playing, got to the point where I could beat the AI pretty consistantly, decided to take on humans. Expect it to go about the same (i.e. Get beaten pretty regularly for a while, then get better until I can beat them consistantly)...
2. In the single player, I took all the things people mentioned here about transports to test, and you will SMITE the AI if you use the transports they give you in the campaign scenarios effectively, so transports are pretty high on my target list...

(Old addage: If you know what beats YOU, it will generally hurt others, too)..
All in all, I look forward to it, heh. Can't learn without losing..
Me.