what bonus do veteran units have?
does that mean they will be 2.1.1 instead of 1.1.1?
Veteran units have a 50% bonus, so 1.5,1.5,1 instead of the standard 1,1,1. Normally a unit becomes a veteran after 3 victories (or a single victory over a more powerful unit). They also get some sweet graphic changes, which are dependent on the civilization -- a Roman warrior upon becoming a veteran receives a traditional Roman helm with horsehair crest, whereas an English warrior receives a Saxon skull cap.
After another 3 victories, the unit becomes elite and receives a special bonus (you'll be presented with with a choice of two more or less randomly chosen from the table
here down in the Units, Military, and Combat Section. I say more or less randomly chosen, because different types of units are limited in possible promotions -- defensive units can receive Engineering or Loyalty, whereas Artillery can't and receives Blitz or Infilltration. With elite promotion you get a second graphic change and a little mini-icon on your unit portrait. You can continue to get special bonuses every 3 victories.
Finally if one army defeats another army of roughly equal or greater power, sometimes your army will receive an Army General. This is cause for great celebration. The General will give every unit in the square a 50% bonus on both attacks and defense. (And has a nice little Visual, showing up in the square for battle either on a horse or in a jeep).