Apple could kill sign up forms on iPhone.
If I have to code one more sign up form for iPhone I'm going to punch a hole in a wall. Heck, if I have to fill out one more sign up form on iPhone I'm going to go ballistic. Sign up forms are tedious, and it doesn't help that every app's flow is different and most are poorly designed.
But Apple has the power to solve this by making sign up forms one click. They can supply the email address of a user, as well as a name, birthday, and whatever else iTunes knows about us. They wouldn't need to give the user's password, just give a hashed version or use the UDID. If I had to enter my credit card information every time I had to buy and app I would almost never buy apps. If I didn't have to fill out the same freaking form every time I download an app I would try out more apps.
This is not just a viable alternative to Facebook connect, it would be better because every single person with an iPhone has an iTunes account and not everyone has Facebook (or wants to use it). Moreover this information will already be validated by Apple and will have far less typos. If I had 10¢ for every time someone typed gmail.cm instead of gmail.com into our signup form at Yobongo we could probably IPO.
We spent a rather ridiculous amount of time on our sign up flow at Yobongo (which incidentally has had overwhelming positive response), but I can't help thinking how much better it would be to eliminate the sign up form altogether.
***Update
I realize this is similar to gamecenter. I'm suggesting that they expand the concept into something which would be more generally applicable.