the problem is that if third party publishers believe that the PS3 will take the lead in a couple of years, they'll keep developing for the PS3. So long as analysts (who really have no idea about anything) keep making these predictions, then the publishers who pay big money for their analysis will continue to make PS3 titles while putting token effort onto the Wii.
From there there are really two scenarios. Either enough TP's do that that it becomes a self-fulfilling prophecy and PS3 takes over, or all those third parties lose millions on their PS3 projects and move development away from it.
While the PS3 victory scenario is still possible, I think that anyone who actually thinks it's the most likely result is a little bit crazy. I hope to see in 3 years a whole lot of analysts losing their jobs...
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