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1440p would be a logical next step for home theater.
2560x1440 is exactly twice 1280x720, which elimates upscaling artifacts. Ofcourse now you'll get them when watching 1920x1080 content.
If blu-ray goes anamorphic for 2.35:1 movies, ie storing the movie at 1920x1080 instead of 1920x810 with black bars, you will get the full vertical resolution on a 1440p screen. Only the horizontal resolution will need to be scaled up to 2560 to get the movie in the correct aspect ratio. This is also compatible with 21:9 tvs with 2560x1080 resolution.
Or you could go straight to 3840x2160p if you have 70k to spare...
http://cave.hometheaterhifi.com/group/hdtvs/forum/topics/welcome-2010welcome-2160p
At least both 720p and 1080p content can be displayed without any upscaling artifacts, but you'll have to wait until hvd comes out to have any real benefit. Or use it as a pc monitor.
For 2160p to be of any use at 10 ft viewing distance you will need a screen of at least 100 inches diagonal, for full benefit it would need to be 150 inches diagonal.
The tv displayed here is 82 inches, sit further then 5.5ft away and you wasted your 70k.
