We are hoping that Roland will be able to implement the software improvements - primarily the improved OTS implementation and the .txt/.bmp style and song link (and Mark/Jump improvements), but it is EXTREMELY unlikely that Roland will ever do a hardware mod to bring the G70 up to E80 specs. That just isn't Roland's style (in fact, NONE of the major players - Yamaha, Roland OR Korg - ever do hardware retrofits to turn, say, a Triton into a Triton Extreme or a Motif into a MotifES or, dare I say it, a Tyros into a Tyros2).
In fact, although I think it would sell very well to G70 owners, I really doubt that Roland will even do an SRX board with the E80's extra sounds, to make it style compatible. The big 3 just expect you to sell off the old hardware and buy the new. Now Kurzweil, THERE was a company that went out of their way to allow you to retrofit older models to have the new features, but look at what happened to them...........
My guess is that by Winter NAMM or spring Musikmesse, we will be seeing the E80 electronics in a G70 form factor.
_________________________
An arranger is just a tool. What matters is what you build with it..!