No. If you buy a 1.0 copy, you can throw away the disks but keep the code. When ARR is released, you can register your 1.0 code, and that will entitle you to a free copy of ARR.
The only time you have to buy a new copy of the game is if:
1. You never purchased 1.0 at all, ever, or you never registered your copy of 1.0 and have since lost the box with the code in it
2. You want to play on PS3. Regardless of whether you had a 1.0 copy or not, ARR on PS3 will require a new purchase of the game.