Still, the move is quite surprising to me and very brave. We shall see if it pays off. This announcement will doubtless have quite an effect on the game industry for at least the next year. What sort of effect ... that is more difficult to see.
As a Paizo 'Superscriber' (i.e. I'm subscribed to all their game related product lines) I plan to keep up my subscription regardless of edition. I enjoy their writing, their production values, their consistent innovation. I have no problem converting systems.
Who knows ... since I'm going to almost certainly end up owning both 4th edition and the Pathfinder RPG maybe between them I can house rule some amazing hybrid.
I'll get my first real hands on taste of D&D 4 at Gamestorm. By then, I should have read and fully digested the Alpha release of Pathfinder. Then, I may have more to say about this.
Always in motion the future is.