Totally right. Sales aren't the only factor. It can matter for developers targeting users, though again not the only factor.
In particular, as a developer, I'm excited about the opportunity to have solid multitouch on a bigger screen.
The first example that comes to mind is the fact that numerous games and other apps aren't possible on the iPhone/touch because the screen isn't big enough, such as two-player games on the same screen.
Does this add options to the market? Yes. Is it a game changer? Not even close.