(The following is a re-posting of thoughts I posted to the GOSLING mailing list in response to questions about why the government created the Open Government Licence – Canada rather than adopt the generic Creative Commons or Open Knowledge Foundation licenses)
This OGLC license has an advantage to the government in that the license itself answers many of the most common misconceptions (IE: privacy, third party rightsholders, non-copyright rights) when dealing with government data that doesn't seem to come into play with other knowledge sharing.