Alone in the Dark: Near Death Investigation is being made for the 360 and PS3, but will have a version made for the PS2.

And what's left out, aside from the ghastly 480p? Well the scale isn't as large, AI scripting is reduced (I call it that, since real AI is years away), and physics aren't quite as complex.

Yet guess what? The gameplay is intact. How is that possible? You tell me. 

It's probably comparable to a DS/PSP release alongside a PS2/PS3/360/Wii release kind of like Harry Potter: Order of the Phoenix or the Madden games.

No da.. theres a version mercenaries 2 coming to the PS2 too. They are just going to use the PS2 Mercenaries 1 engine and modify it a bit to use low scale Merc. 2 textures and stuff.

 Well for all the comments about how Wii versions supposedly couldn't "do justice" to a game made for HD systems, it proves them wrong to see that even the venerable PS2 can do justice to those games, simply by using what it already has.

I can't wait for Nippon Ichi's "Soul Nomad" in August myself. Between that and MP3, I'm gonna be busy. ;)

 Its not really doing justice to the game, its using a weaker engine to port a game to a weaker console, so really if Merc 2 was going to go to the Wii it would be running on the PS2's engine. 

In this case you're probably correct in assuming any version the Wii would get would be based on the PS2 version ...

In general though if you were starting a new game today there is nothing that would prevent you from building the game based on the Wii and then improving it for the PS3 and XBox 360. If you increased the geometry in objects, increased the resoultion, used advanced shaders and displayed a game at HD resolutions you would use up a large portion of the extra processing power of the PS3/XBox 360 ... For a large portion of games this would be adequate and you wouldn't notice the difference between the game that was started on the Wii compared to the game that was started for the XBox 360.

 But this is about games made for HD and downgraded, not upgraded to HD.