PS3 will only catch up if it makes some big changes in Japan and starts selling good software there. Otherwise it'll always end up selling less in America and more in Pal regions but never enough to make up 71 million in software over the next 3 or 4 years.
Edit: Also worth noting since you got those numbers from this site, a large portion of the 360's sales in Europe during 2005-2006 aren't even included in that since they are very incomplete.








