There are obvious work arounds as mentioned but will cost you money since you can't have the same number on two phones. The problem with work arounds is they all seem like a pain in the big A. I'd just wait until you can look at and handle both the new iPhone 6 (4.7) and the iPhone 6 Plus (5.5). Maybe it won't be that bad. I feel I am committed to the 6 Plus because the optical image stabilization comes only on that unit and the bigger screen will be all that much better for photo post processing. I don't use an iPhone for talking but more for email, texting, apps and camera. If it fits in the pockets I want to carry it in, I'm there.
I think they will cannibalize the iPad Mini and I hope Apple comes out with a 12" iPad for my next tablet.