They'll probably switch to a magnetic connector and save on all the repairs. Miniaturization has always been the goal in technology hasn't it? There will be an adaptor I'm sure but it will cost extra. The only thing I would need the adaptor for is my camera connection kit. I stopped buying dock connector accessories a long time ago knowing this would eventually happen. I use Bluetooth for speakers etc and apple tv wirelessly for video.
Of course i'll have to buy new cables (or 1 adaptor) for syncing or charging in the car but it is what it is. Things change, it's unavoidable. Mini to Micro USB was the same thing, had to get new cables.
I don't actually see me upgrading anyway considering I paid for an unlocked 4s.