Hitachi's crt based sets do accept a 720p signal but will not display it natively. They convert 720p input to 1080i.
Hitachi's dlp rptv will not only accept 720p, but will also display it natively.
In fact when fed 1080i they convert it to 720p. These sets are very hard to find and also quite expensive.
There are currently very few HD ready CRT sets on the market that accept 720p including the Hitachi mentioned above..The set top box's on the market will take a 720p signal and convert it to 1080i for the vast majority of HD ready crt tv's currently on the market.. ABC is the only broadcaster doing 720p...Everyone else is 1080i...
Most HD ready RPTV will accept 720p but most convert it to 1080i before displaying it. There are some that will display native 720p but they are up there in $$$.