Will the maps be randomly generated like previous diablo games? The beta showed a set path every single time. (read linear)
The beta was still random just not as much as the rest of the game obviously due to them wanting to have a small area and not overwhelm people (this question has been asked and ansered before in other Q&A's)
The beta was still not linear, you just thought so. It may have only seemed linear because the pieces that made up the randomly generated jigzaw puzzle were very big.