I think it could be announced in 2010. Even though a lot of Nintendo fans want the Wii to last forever, Miyamoto himself said they would have to keep up with trends in technology. So, depending on hd television penetration into homes in the next couple of years, that will have an impact on when it is released.

I believe Mr. Iwata has already said he has no interest in making an incremental upgrade that is basically the existing Wii with HD tacked on. 

If they are releasing a new machine it most likely is because they're concerned about Natal/Sonywand and the general increase in HD console sales eventually eating into their own potential consumer base. 

So I think they would definitely at least match the 360, otherwise there's really not much point. I suspect they will study the Natal camera in particular quite carefully. 

Fall 2011 at the absolute earliest, and even then I don't think it'll be likely. As long as the Wii continues to sell well, Nintendo will put off launching the Wii's successor for as long as they possibly can. 2010 also has a pretty big lineup of releases for the WIi like SMG2, Metroid: Other M, and in all likelyhood, the next Zelda just in time for the holidays.

I also think Nintendo is going to hold out and see how well Natal and the PS3 "wand" perform before... if they really take off next year, then fall 2011 is a definite for the Wii HD. If not, then perhaps sometime in 2012.

I could be wrong, but the only reason I would expect Nintendo to release a console in 2011 would be to capatalize on the continued popularity of the Wii while taking advantage of new very powerful inexpensive hardware ... The point would be to produce a product which was difficult for Sony and Microsoft to make meaningful improvements on (at least) a year before they brought their product to market; essentially, they would be trying to emulate the success of the PS2 where the generation was "over" before Microsoft or Nintendo could bring their console to market.

Iwata is not Yamauchi, I think it's an significant difference.

Yamauchi would ride the Wii and probably not release a new machine until 2012-2013 even if it meant surrendering a ton of marketshare.

Iwata doesn't really work that way. He watches week to week and month to month sales very closely, not just "well, we're making a profit, lets not do anything".

Last year they introduced the DSi because in Japan the PSP was starting to outsell the DS on a consistent basis and sales were way down in Japan even though sales of DS Lite were great in North America and Europe and NOA was even reportedly not happy with the decision to unveil the DSi. People also said Nintendo would never cut the price of the Wii ... yet sales are down year-over-year and Iwata takes action. 

I think Iwata understands something Yamauchi didn't -- if you allow competitors to just walk in and take market share uncontested eventually your profit margins will feel the pinch too.

Maybe the better way to look at it is this -- the only way Nintendo doesn't release a Wii 2 (I hate the name Wii HD) by 2011 is if Wii sales continue to increase year over year and Natal and Sonywand are both bombs. But even that, I think Nintendo has noticed this year that sales of the HD consoles are up, whereas sales of the Wii are down ... that indicates more people are buying HDTVs and eventually wanting an HD console. Nintendo is not going to ignore that market forever as it becomes more mainstream. HDTVs are now dirt cheap -- they were not in 2006. Something Nintendo also has to consider. 

On the gametrailers ARE THEY IDIOTS? I mean, really, Modern Warfare 2 doing better then Mario Bros? No, or at least not easily as they implied. Modern Warfare sold ~11 million units. New Super Mario Bros Wii sold ~19 million. Mario is huge.

Is it possible that it could happen. Yes, but in order for it to, buyers would have to get bored with it for being to similar to the DS one and Modern Warfare will have to still stay strong (World at War only did ~8 million between two systems).

if you guys had seen him youd have known he was being sarcastic cos the other guys were taking the piss out of him

The Wii was always the console that would give ground first in my opinion. I expect it to be a modest upgrade of the existing Wii though making it easy for the Wii faithfull to follow through to the HD era.