For once, I have to disagree with you Doc.
Here is VZW's International Text Messaging page.
The key text we want to pay attention to here is:
While traveling outside the U.S., Canada, Dominican Republic, U.S. Virgin Islands and Puerto Rico the text messaging rates are:
That is to say any text messaging done INSIDE Canada would be charged normal domestic rates. It's only calls that are charged at .69 per minute.
A CS Rep can confirm this for you, but make sure they take the time to research it if they're not sure or tell you off the bat that's it is an additional charge. Often times people are quick to assume there is an additional charge simply because it's another country.
This specific question is one that has come up many times in the forums, if you do a tag search for Canada or International Text you'll find many examples where I've posted this information.