If what you say is anywhere close then it would do two things,
1) make the G1X superfluous and be competing in a way with the new EOS-M
2) at the price level you quote it would no longer be a successor to the Canon Powershot Gxx line
anyway Canon already introduced a two Pro models recently they are called the G1X and the EOS-M respectively!
I don't think crowded is a bad thing for Canon in this second of the market, with the decline in compact sales/profit this is likely where a large amount of the profit is for all the big manifacturers.
IMHO if it is really to be a Gxx successor it will be in a G12 type body possibly with the edges smoothed off,(love the EOS M design), APS-C sensor at about 14 to 16 Mpxs, same folding screen, broader zoom range, say 24 to 120mms I would hazard a guess at 8x max, it cant go much more than that or it will get too big and not be able to retract into the body. I think they might introduce the same touch screen as on the EOS M to get rid of some of the knobs and of course Digic 5 processor.
Personally the video doesn't interest me but I guess they will throw in the best available they can off without cannibalising the G1X or the EOS M I also reckon the price will be around the $600 to 800 range so as not to compete with the G1X.
I can definately see something with a sensor size between the G1X and the G12, perhaps with a longer zoom aswell?
As far as a fixed L lens goes I'd guess Canon would only go with this if they came up with a really prenium product and needed that extra push to sell it, say...
70D 22MP ASPC sensor.
24-70mm f/2.8 quivilent with manual zoom and filter ring.
Over 100% coverage optical veiwfinder.
Fully weather sealed.