Well, it's more like a double-edged blade: it does help exports and foreign investments, but makes life more expensive when it comes to importing.
So, how much does Canada import?
How much does Canada export?
It's a dangerous economic tool, and that's why one of the first steps in the EU was to establish a common currency, to avoid countries exploiting the devaluing of their own currencies.
Sure it's a great tool for the US to stay competitive and especially considering their foreign debt.
I don't want to start an economics debate, just wanted to add my 2 cents as we're already experiencing the other side of the coin on our wallets (provided that games should be considered as imported goods?).
The argument that it is good for the economy when our dollar is weak always bothers me. The only people that will benefit from it is going to be the top people of companies and the companies themselves and it well never reach normal individuals. It won't mean lower unemployment, won't mean people will get better pay because a company makes more money. We were never hurting when or dollar was at parity, and the most amount of people benefited from it, just wish the government actually did things that would benefit us over companies. Sorry for the rant.