for viewing distance of 10 feet 720p will be a wiser choice for following reasons,
1) Broadcast is 720p and 1080i only, (native resolution of 720P sets)
2) for Bluray movies if interlacing is done on set correctly there is no difference in PQ between 1080p and 1080i.
There is one issue though most of the 1080p sets have all the advanced features because manufacturers will get more money for 1080p sets, 720P sets will be considered as bargain sets in near future with less features, manufacturers will do 1080p for sizes 37 and up and put more advanced features in these sets.
Home theater Magazine did a very interesting test between tvs from every technology RP, LCD and Plasma, in their test Pioneer 720P plasma beats all other 1080P sets, Pioneer processing of pictures were far better than any 1080P sets compared. I would pick a Pioneer Kuro 720 plasma over any 1080p LCD.