when facebook changed user profile pages to be more stream-centric than app-centric, developers complained too, and subsequently destroyed the user base for a few apps that relied on user profile canvas presence. However, I think the change was for the better and the good apps that survived focused more on the user stream than a flashy annoying front page widget.

I think anyone developing heavily for one platform should always keep in mind that you'll need to pivot as quickly as the platform company.