ToMI is a TellTale Game.
ToMI on the WII is a severely shrunk down and compressed version of the PC version.
ToMI is "too old" for PC? Why? It looks fine to me, and some people still can't run it. Not everyone upgrades their pc often and it's almost scary to know what kinds of pc's people still use. And these people could very well be Monkey Island fans.
So, game looks good for all of us and is runnable for a very large userbase.