5) IOS4 vs IOS5. Come on Apple, I am begging you to not
  turn IOS into the next Internet Explorer.

I don't see how you can avoid this and without incurring the fragmentation you find in Android. We should expect Apple to continue with the measured iOS migration and sometimes not so subtle push to get us devs to move the bar forward. Interesting to see how Mountain Lion will force a move to XCode 4.4 (my guess) and Apple will bury the older SDK's ever deeper in their website.

I really can't fault Apple for this approach.

BTW, we rely on Flurry data to judge what the economic cost of choosing a new iOS target.