But I bet this myth that 3rd parties tank on the Wii will still persist just like the myth of the N64 and Gamecube barely being profitable for Nintendo.
3rd party Wii titles did sell poorly for a very long time, don't mistake that. As for the N64, the complaint was always that the N64 was very profitable for Ninny... and the GCN we don't know how profitable it was as the GB/GBA and initial NDS sales were massive and carried the day substantially.
Back on the Wii, we need to factor in the positives (small dev costs, shorter dev window, bigger install base) with some of the negatives (games cost 33% less, royalties are a bigger percentage of profits, you STILL have to advertise the game which is a significant cost, per-unit attach rate is lower, inability to port to PS3/360, unique and at times confusing software adoption patterns, many establish franchises cannot rely on recognition alone as a safe gamble for significant investment, great reviews/top 5% games have met significant commercial troubles, etc).
In a nutshell, for the Wii, it is all about the type of game you are making. There are more variables a recouping the investment on a $20M game can be difficult if not managed well. So while initially it was, "Doh! Wii owners are buying few 3rd party games" the issue is now more, "What games are appealing to Wii owners? What is a safe development pattern to recoup investment?" That said the Wii has a huge amount of shovelware and as the install base continues to outpace the industry their sales, even with a lower attach rate, will continue to increase. This is something that was discussed a lot in 2006 in the price drop threads: are you better off with 20M units with an attach rate of 10 or 40M units and an attach rate of 6? The answer to that question is complex, but from a corporate perspective the first question would probably be, "Do I lose money on each console unit sold?"