Man I get tired of saying this. Its not art that costs more in HD games. Its engineering, and has been, at most, 2x as much to develop on the PS360 combined than it is to develop a decent Wii title. You get what you pay for. No such thing as free lunch. I could go on and on.
Most of the time, a good PS360 game costs about 1.5x as much as a good Wii game would. The huge amount of shovelware brings down the Wii's average cost -- not some magical ease of development. Ambition drives cost more than anything else. A game doesn't need to be ambitious to be good, but it helps.
The only time this rule gets broken is when a new (read: cheap) development house breaks out with a hot new game. Most of the 3rd party successes, thusfar, on the Wii fall into this bucket, because, at the time these projects got started, only the "B" teams were getting assigned Wii projects.
That's no longer the case. Western (I know nothing about Japanese studios) Wii budgets have already gone up (pretty much everywhere), and you'll see the results in about a year.
