Joe and I got together today to try out the WAB 2 rules. Joe has the rules and has played one game already. I do not have the rules and have never played the new version.
Joe brought his Celt barbarians and I took my 2000 pint Northumbrian Saxon army. The table was mostly open. The terrain generation system seems to favor a table with little terrain. We play a simple pitched battle type game and since we both had foot armies we deployed 12" in.
The battle was very fast and very simple. Joe moved very quickly across the table and was in charge range on turn 3 (top). I only moved once and then went into shieldwall. The game consisted of one round of combat and that was it. We had 4 combats on turn three and Joe won 2 and I won one and the fourth was a draw due to a stubborn unit. The two units of min that lost combat were destroyed and the one unit of Joe's that lost was also destroyed. I lost a couple more units due to panic and the game was over.
My overall impressions of the game are positive. This game was much quicker than I would have liked but it worked to introduce me to the new rules. I learned quite a bit about the game. The first thing I learned is that skirmishers are not worth much. Because of the new army break-point rules they seem to be more of a liability now. The reduction of the rank bonus from a max 3 to a max 2 means that most of my units are now too deep. It seems like wider and shallower units are the new norm. Another change brought about by the change in the army break-point is the need for more units. Having a small number of large units is not longer an advantage - more small units is the way to go (I think).
So those are my impressions after a single and game and having not read the rules. I need to order the book soon so I can get a better feel for the changes. One thing is clear, this is a different game and your old armies and play style may not work.