Consumer confidence is a fickle thing. For instance American cars developed a pretty bad reputation in the early 80's, and Japanese cars developed a good reputation. It's debatable now who makes the better cars, and has been since at least the mid-90's but there's still a widespread perception of American cars being much more unreliable.
People claim that it doesn't really matter all that much who's number 1 in the console race, but it does - due to the special nature of the business. When a console is #1 in sales it increases confidence directly through the logical assumption that the most popular console will have the widest selection of games available, and development will continue for a longer period of time.
I can see how it would be possible to have a perception of the X360 as the most popular but losing ground, increasing the likelihood of the release of a new console (thereby making your current "investment" obsolete). However, seeing a console like the PS3 which is gradually gaining steam would suggest that it's going to be around for a longer period of time. The Wii sales are just so high, and the development cost so minimal in comparison to the PS3/360 there's not much question of its continuation as a platform, especially considering Nintendo has a very good track record with backward compatibility (the Wii is more compatible with the GC than the PS3/360 with the PS2/Xbox, the DS is compatible with the GBA.
One issue might be with the PS3's choice of the Cell however. Being such a strange architecture, and the reported difficulty with development it's entirely possible that Sony might completely abandon it in the next generation - and it would be unlikely that it would be a realistic candidate for software BC if they return to a more traditional symmetric architecture.
