At this point it doesn't matter if the next console is in HD. Nintendo will still be crapped on by most 3rd party developers. Only a few would put serious efforts on the console. It's been that way with the N64, Cube, and now the Wii. People like to claim it's a conspiracy theory but there is no other way then to look at it I think as a industry wide plan to hurt or freeze out Nintendo.
I would hope Nintendo will simply forget about the rest of the industry. Those that do want to work with Nintendo in a serious manner should be given access but screw the others on the system. I have all three systems (for specific games) now but I think this is the final time I do that as I'm gaming less and less as each year passes. Nintendo will be the system I stick within the end though if it ever came to a point where I'd only buy one system and that's it.