I bought the updated DVD for our 2004 Honda Odyssey, and the 2.20 version arrived on Friday. I was hoping that, in addition to the updated maps, it would include some software fixes like improving searching speed.
The upgrade went very well, with no problems. We didn't drive to any areas where the roads have change recently, like around the San Jose airport, so I don't know if the maps are significantly improved. But we did notice a speed improvement when searching for places. The other thing that they added is that when getting directions, the navigation shows the exit numbers when directed to exit a freeway.
Update 10/31/09: I have disabled comments on this post, as the majority of them were about getting illegal copies of the navigation DVD.