The new regulations by TRAI does not mention anything about regulation of voice apps (or about slow/fast lanes).
I think you have misinterpreted the comment by SaveTheInternet.in. What they're saying is that while differential pricing has been dealt with in accordance with NN principles, there are two more battles which are going to be fought i.e. i. Defeating the proposal to regulate voice apps ii. Ensuring that no slow/fast lanes are there on the Internet.
Its a "yes, we won a major battle but the war is not over yet" caution. Not an indictment on what TRAI is going to do for voice apps & slow/fast lanes.