You know, all things considered, it's really hard to pick any one team that has the "best" fans, especially in the west. Despite the rough patches for most teams (been a while for Edmonton!), they are all still in business and doing reasonably well. Any team that is loved enough to stay in business is doing well at attracting fans. And as has been stated by others, every team has their story of die-hard fans, idiot fans and band-wagon jumpers.
As far as the actual numbers go, there are any number of factors - weather, city/stadium size, history (Edmonton's solid run of playoff appearances definitely helps!), team's record, etc. Plus, attendance doesn't necessarily show how many were cheering for the opposing team (how many in Calgary this week will be cheering for Sask?).
In my opinion, it takes up too much energy to fight over the best fans when it's such a subjective issue. I'll cheer for the Riders, and you can go ahead and cheer for the Eskies. I bet neither of us will ever change, and that's the way it should be.
By the way, EE, I noticed that of all places you could have posted this, you chose the Riders fan site (along with a good dig at us!), then you make the comment that there's a lot of hostility and envy in here. Hmmm...sounds like someone is trying to jerk some chains....
:D But I will gladly grant that Edmonton, like the Riders, has some truly great fans. Keep cheering hard!