3x or more what you are seeing with 11b/g if I recall...but the most signif aspect of the improvement is not the "line of sight" distance improvement...it's the "through the obstruction" improvement.
For example, try to get a WiFi signal across a yard/neighborhood/park dense with trees.
Make no mistake about it...there are plenty of home users that will welcome .11n
Not to mention the Muni-WiFi and Campus-WiFi project advantages it will bring. There would be a whole lot less units & repeaters that would have to go up to cover the desired areas.
So when those areas dictate .11n then suddenly the average user will have even more incentive to go to .11n for compatibility.
Of course WiMax may change that whole picture in not too long. | 
