I look at the .ca extension the same way as I look at .co.uk.
I don't compare them with .com, I just rate them 'up there' along side the .com market, except in the country of which the extension falls.
.co.uk is a massively used extension within the UK, and I'm just sure .ca is as big in Canada.
There just extensions on their own level, as I see it. Some are worth alot, others; nothing.