Hey VegasVec, I don't know how much help I can be on most of these but I'll try with a few to help you get started...

1) Either M80 or M60 would work. M80's simply play LOUDER. They would be more appropriate for large rooms where you're sitting a fair distance from them or if you're a person that prefers to listen to their system at deafening levels. If you're sitting quite close to the fronts say within twenty feet the M60's would do you just fine. But if you're further away than that, love your music really loud, want Axiom top of the line speaker, and $$$$$$$$$ is no object then the M80's would also be awesome. There's really no sonic advantage of the M80's over the M60's other than decibels.

2,3) For the M80's Alan has recommends Denon, HK and newer NAD recievers or separates. I'd also say Outlaw would be great too. The M60's would also work great with these but others have reported great results with Yammie, Onkyo, Pioneer. Can't say about a 8.1 reciever as I didn't look for one in my recent search for a reciever.

5) Ceiling speakers. Foreign territory for me but I'd wager either the Qs4 or Qs8 would be your best bet.

6) IMHO, save the $$$$$

7) For a system like that you'd likely want a big sub. HSU, SVS and Axiom all make great subs. Axiom subs in the past have always been well regarded and very good performers but with the competition from HSU and SVS likely haven't offered the same bang for the buck to US customers as their other speakers, for Canadians this is a little different senario. The new EP500 and EP600 may prove the be Axiom's "break in" subs, only time will tell. The EP500 and EP600 would likely be more appropriate for the kind of system you're talking about. I just recieved the EP500 and I"m LUVING it! It truly can reach to the depths of Hell!

8) There are differing views of whether even 6.1,7.1 are much of an improvement over 5.1. So 8.1 I don't know as I haven't even got my 5.1 setup. My advise would be to start a bit slower. Go with a 5.1 setup and enjoy that for a bit then try adding some more speakers to your system. If they don't give you the increase improvement you're looking for then you could easily return them within Axioms 30 day return period.

Also don't hesitate to contact the Axiom folks like Alan as they are very helpful from begining to end and post sale. Particularily on the 8.1 issues.

Welcome and happy Home Theatring, Jag