Canadian Idol is a copy cat of American Idol, which is itself a copy cat of the U.K. version of the show. Not that that's a bad thing, but it's just not very original.
The Canadian version is pretty much the same as the American one as well. Last year, it was different, with the top 32 being split into groups and a wildcard selection; this year, it's exactly the same as the American version. I don't really know which way I like better. The wildcard was a good idea, because some good singers got into the competition that way (Aaron Walpole), but the top 10 is the format that I'm used to from the American show.
The best part of the show is probably the audition process, where they show all the really bad singers. That's usually good for some laughs. Once they're into the top 10, things start getting serious, although there can still be some pretty bad performances when the singers choose a song that just isn't right for them. But for the most part, they do pretty well.
Overall, it's an okay show, but it's really just the same as the American Idol.