Felt the need to ask around about the Junos and here's a response from my cousin Adam, who works for The Agency Group, which represents these artists.

Here's his two cents:

The Juno’s are picked by the board of directors of an organization CARAS. Everyone in the CAN music industry is a member of CARAS including me. We all get to vote for “Best New Group” but that is it, the board picks everything else. The board is made up of some old school-ers in the business. It’s bogus we all know it, but a couple of my bands are nominated and I could use some more hardware in my office. Oh yes, I have a Juno on my desk!
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There you have it! Apart from the New Group category, a board of directors made the selections. They seem to be as on the ball as 'the board' of strategists who ran Paul Martin's election campaign.