Is it possible for Nintendo to release an expansion pak or firmware update to have games display in HD?

If it's possible I think it would lengthen the Wii's longevity.

Doesn't work that way--every single game would need to be patched with new textures to take advantage of it.

That said, you can get component cables to display the games in 480p.

Arguably they could release some sort of upconverter.... but firstly HDTVs usually have their own (though they can be low quality) and secondly it still won't make the games look any better than it is possible to now (as long as you TV is set-up correctly)

Is there anybody who really cares? Doesn't matter if it's in 480p or 720p, it's the same bloody game and will be equally enjoyable regardless of the resolution!

Super Mario Galaxy or any other Wii game would not be more fun in 720p, it would simply be the same game in a higher resolution.

Let's move on people!

On paper, the Hollywood GPU is entirely capable of outputting 720p or so. A game would have to be made that would do it, but conceivably Nintendo could release a firmware update to get all the menus and such to run in 720p also.

Of course, paper =/= practice. Much like the Saturn was the most powerful console of its day on paper, but hardly ever showed it.

They could in theory unlock the ability for a developer to output 720P (the hardware should be capable). But due to the lack of memory space this wouldn't work to great at all and you would get lousy frame rates.

I meant to display the Wii graphics upscaled to at least 720p using a firmware update or other means? Is it possible?

no for the same reasons posted above. The hardware would have a tough time handling that much data. Why waste processing power up scaling when you can let the TV handle that.

Not if they upscalled.

A good TV should upscale the image for you anyways. LCD TV's can only display in their native resolution, so they must upscale. With a good built in upscaller there is no need for the Wii to upscale.