After the initiation of IPL, a lot of experiments have started happening in the cricket game to make it more attractive. That's good because it is helping to boost its popularity around the world and new players are coming into limelight.
The T20 format is also initiated and developed by ECB in 2003 and then the initial world cup was a grand success and India won the first tournament which changed the format popularity and before that ICL tried to take advantage of the popularity but BCCI killed that initiation and started the IPL copying everything the ICL was doing and now ECB is coming with another format which might interest the fans.
I don't see a lot of changes in the actual format here. Instrad of six balls, there will be five balls per over and a bowler can bowl for two consecutive overs. Hopefully it will give some edge to the bowlers as opporsed to the bastman.
There is no way the shorter format will be designed to help the bowlers as they want to have audience seeing the ball disappearing in the stadiums rather than seeing the sight of batsman struggling.