At the design review held at FSG the past week, Pat Clarke and Owen Carless confirmed some of the 'rumors' about the new rules for 2015. I'll sum up from what I heard, but in details I might be wrong.

Aero rules:
The rules for the aerodynamic devices such as wings and diffusers will be tightened again. According to the 2 chief judges, a few years ago the aero rules were loosened so that more teams would venture into aerodynamics. This was done because the rules commitee was of the opinion that too little research into aerodynamics was done. They now feel that the time is there to tighten the rules again and make it a bit harder to create a beneficial aero setup. In what shape or form these rules are was not discussed.

4WD electric rules:
There will be a drop in power for 4WD electric cars. How much was not specified and is not known yet.

Design Scoresheet rules:
Pat Clarke and Owen Carless made the 'announcement' that FSG (maybe FSAE? not sure) was looking into evolving the design scoresheet to better reflect current rules and regulations, especially considering the electric vehicles.

I'm only paraphrasing here, so I might have one or two exact details wrong. It would be nice if either Pat Clarke or Owen Carless would comment on this