Excess speaker wire

Coiling shouldn't have any effect, since it is cable and not a wire.  Coiling single wire increases inductance, but coiling wire and return doesn't - because both wires in cable create canceling magnetic fluxes (opposite direction of the current).   Non-inductive wirewound resistors are created by folding wire in two and winding pair of wires with ends on one side (bifilar winding).  Winding wire and its return also creates "common mode choke", that has inductance for common mode signals and no inductance for normal (differential) mode signals.  Coiling power cable, especially on the core, creates such common mode choke filtering out electrical noise induced in both wires with no effect on regular (differential) operation.

Thank you all for such an informative and detailed responses. At the moment I am running the excess length in a zig zag, figure of 8 fashion and it seems ok for now. However allthe excess wire is on the floor underneath my hifi racks unit, right underneath my Luxman integrated amp. 

I'll have to unravel it one weekend and see if I can hear a difference..

No excess length!

A copper wire resistance equals to Ro (the metal conductivity constant), multiplied by its length in meters and divided by its cross section in square millimeters.
The longer the cable the higher is its resistance...
You should have speaker cables as short as possible, to keep the resistance as low as possible.
The shape of how you lay the extra length is not v big deal. the extra length IS!

Thank you b4icu442. I have no intention of cutting my cables as they are factory terminated and cost a lot of money (for me). Good to know that the shape of the lay is not a bid deal. One of these days I'll have to route them under my floorboards.
Good to know from all the answers that it is still a hot topic!