[citation][nom]mrmike_49[/nom]Is that true ?? Both NBC and CBS use 1080i, while ABC and Fox use 720P, AFAIK ()[/citation]
Yes, 1080i is roughly the same bandwidth as 720p. However, 720p is far superior to 1080i (although this can be debated). You can look up the difference to see why, but the lack of true 1080p content lacks because Cable systems just can't handle it, even compressing the hell out of it, it would just use up too much frequency spaces which would mean they could broadcast far fewer channels.
I'd say we'd be lucky to see 1080p content in 5 years. I wouldn't expect 4K or 8K to hit TV's for far longer than that, unless some major investments are done between now and 2017.