The event is sort of softlaunched, in that the date isn't posted yet. Minister Clement announced it, and later said
The Canadian Open Data Experience – CODE – is a 48 hour nationwide app development competition
The other thing that I announced today, by the way, is our first appathon, where we're going to invite entrepreneurs of all ages next February  to go onto the data.gc.ca website/portal and in a 48-hour period come up with the next app that uses Canada's open government data and develop something that will be of use to citizens
Possibly this will be timed to coincide with International Open Data Day 2014 on February 22, I don't know.
There is a basic signup site at http://www.canadianopendataexperience.com/ and social media
- Twitter @CODE_hackathon and currently the rather overloaded hashtag #CODE
- Facebook https://www.facebook.com/CanadianOpenDataExperience
The government is supporting it, but not running it. It will be run by XMG, who do the similarly-named Great Canadian Appathon (it's not clear if the events will be one and the same in 2014).