there are currently just over 300 million people in the united states.

No.

 480i and 576i are standard definition.

 480p and 576p are enhanced definition.

720p, 1080p, and (ugh)1080i are high definition.

(except in Australia, where 576p is also considered high definition) 

 Enhanced definition will never be mainstream because it was too little of an improvement and has been eclipsed by better technology.

 1080i was not originally part of the specification, but certain tube based television manufacturers found it too difficult to put more than 540 scan lines on their televisions and came up with 1080i so that they could do high def too. Unfortunately, the standard was altered to include it. 

This article is actually very good, as no, it doesn't say that 120 Hz gives smoother frame rate (whatever that means) but that it is specifically made to counter some of the numerous defects of LCD displays. Unfortunately, it introduces others, like completely unnatural movements. These articles are good so that people at least understand that LCD are the worst technologies of all amongst TV. But hey, they're flat and cheaper (NOT! RPTV are actually cheaper).

Back on topic, I don't expect HD to become standard before at least 5 years. I would say in 10 years (so in 8 years from now). But any amateur in the field knows that already, and that's why I know pretty well that people saying the Wii is doomed because of HD are delusional. And I'm talking the currently HD signals here, which means 1080p max.

Someone already explained that TruHD is a sound format, among the mess that is HDTV norms.

And Wojtas, I don't think you understood your brother. There are norms already for HD broadcasts and it says 720p or 1080p. Thoe that broadcast 1080i are not in the norm. 1080i is too poor and harder to compress, so 720p should be used instead of 1080i, as it allows for more quality for the same bandwidth. 1080i is only for TV shows or documentaries on HD media.

There is no super HD resolution foreseen for the home. People that talk about higher than 1080p resolutions for the home:

- don't understand the purpose of HD

- don't understand why these specific formats where chosen

-  probably believe the THX sound they have at home is the same norm that the THX in theaters

To sum up, they're clueless or delusional. Or are drowned in piss contests.

Finally, instead of cluelessly asking for "even better signals", we should rather ask for broadcasters to display 1080p signals instead of 1080i, because we're not even here yet. 

 Not to derail onto an audio tangent, but people generally don't have THX sound at home. They have THX certified equipment. However, to have an actual THX sound system, it has to be configured along specific guidelines and tested for audio quality across the room being wired. Theatres do this to get THX certification on specific theatres for the marketing value (and maybe to entice audiophiles in some locations). 

 I doubt many home theatres have been configured properly or tested for certification. 

 THX is a certification for specific configurations of the environment and thresholds of performance of audio equipment. (sort of like the government security certifications for operating systems. They dont certify the os, they certify the os running on a specific configuration of hardware.)

All that being said, i've heard they are getting to the point where they'll slap the THX logo on just about anything for enough money, so even THX certified sound setups might not be configured properly anymore. 

@ookaze, I'd agree that we're best off worrying about when all channels are 720p/1080p, than worrying about getting UHDV. When UHDV and superb sound quality are the norm in cinemas first, then maybe we can consider transferring it into the home. But before that, then some way of storing it has got to be figured out, as UHDV uses up a lot more than can be fitted onto current formats, ie Blu-Ray/HD-DVD. even 1tb hardrives would struggle to hold more than a few moments of the stuff!

in UK we're only just starting to have digital forced upon us, never mind HD, there is a BBC HD channel, and i think we can get some form of sky HD, but as most of UK wont go digital till 2010/11 [wheras USA does so in 09] i doubt we will have widespread HD broadcasts until 2015.

someone posted earlier that USA is changing to HD in 2009, but its just digital broadcasts then, not HD.

HD-DVD and Bluray aren't going to see the sort of adoption that DVD had. DVD offered a lot of features that VHS didn't have (menus, commentary, scene selection, bonuses) and there was also a flood of content released on it (rereleases of old movies and boxed sets of TV shows).

HD-DVD has no substantial new features aside from higher resolution and there is no back library of HD content. A lot of people aren't going to be upgrading their TV and DVD player just so they can watch 300 with a sharper picture.

 I think this is pretty much wrong.  I mean just try to imagine that it's 2015, and you need a new TV.  Any chance at all they're selling something that's not HD? I don't think so.  And how much do HD-DVD players cost? $30?

I'm not saying people will rebuy on HDDVD what they already own on DVD though...  

 TVs and DVD players can last 10-20 years. There are a lot of people who don't feel the need to buy a new TV so long as their current one is working.

 While eventually HD-DVD or Bluray will start to take over, there's going to be a substantial legacy market for DVD for years to come.