Yes mining will stop one day but we'll all be dead so it doesn't matter. I don't think anything has been decided on the blocks yet but they will need to be enlarged at some point for sure.
I don't understand why everyone thinks that is the best solution to that problem. Why not change the block target time from 10 minutes to 2 minutes. and dive the block reward by 5 for each block. It seems to me that would solve more problems than simply increasing block size. It would allow for more transactions as well as significantly decrease confirmation times. It is not uncommon to have to wait 30-60 minutes for 1 confirmation with the ten minute target currently.
I know it would require a hard fork, but it would be for the better in the long run.