Dzsono: Again, producers have felt that the original light sabre is not cool enough; they've got to add extra bits, a la Phantom Menace...
At first I wasn't too fond of the lightsabre in the teaser, but then a couple of random thoughts popped into my head.
One of the few things I really liked about the Phantom Menace was when Qui-Gon used his lightsabre to cut though the door to try to gain entry to the bridge of the trade federation spaceship, until those attack droids showed up. It showed that lightsabres were useful tools and not just weapons. One now realised that a Jedi with a lightsabre was virtually an unstoppable force and those trade federation guys were right to be so scared of them.
And then we had Darth Maul with his double-bladed sabre, which I didn't really have an issue with.
But looking back at all the Jedi in the films, all of them had standard lightsabres with the only difference being their colour scheme.
So perhaps, in the context of it being the Sith who pervert the original design of the Jedi's weapon, we are all right to get worked up at what they've done... the Sith that is... not Disney.
And perhaps one can take this all the way back to the original trilogy. Vader's lightsabre always looked longer to me than Obi-Wan's or Luke's, so maybe there were subtle differences with Sith-sabres already back then?