Having attended several San Antonio Texans CFL games in 1995 (55-yard-line seats were easy to get), I found it faster paced and in many ways more exciting than the NFL. The obvious differences are that you have a field of 110 yards between the goal lines, a much deeper end zone, and greater width. (This caused problems during the CFL's American experiment in the mid-90's as many US fields couldn't be well adapted to this. The Alamodome in San Antonio was an exception.) The ball is a bit rounder than the US version, as I recall.
You also have 12 players on the field--on offense its an extra back and you have three downs, not four, to gain 10 yards. The plays are paced one after enough more sharply and the all of the backs on offense can be in motion toward the line of scrimmage prior to the snap. It looks wild at first, but it also limits the QB's ability to slow down the snap count or they'll all be 20 yards down the field at the snap, and even in the CFL, that's a penalty!
Kicks are different too. There are no fair catches and kicks out of that bigger end zone must be returned out of the end zone or the kicking team gets one point (often called a "rouge" or a "single").
We saw the Calgary Stampeders come to San Antonio in 1995 with Doug Flutie at QB. When the Texans pulled out to a lead, I told my then-7-year-old son not to get too confident as I had seen Flutie lead too many comebacks, including one against Alabama in 1984! He added to his list that day and Calgary went home with a win.
My son still has a San Antonio Texans license plate clock in his room.
BTW, if you need a football fix beginning next month, ESPN 3 (the old ESPN 360), does carry some CFL games.