And picking and choosing which broadcaster's debates he attends is slimy. However, I don't think it means much. 5 debates are better than 3, and I can't blame Mulcair for wanting to a) raise his media exposure that has never rightly be granted to him, and b) a few more opportunities for him to make fools of Trudeau and Harper.

He will be the Dreadnaught in the debates.

Edit to add; Trudeau supporting all of Harper's draconian police state laws, keystone, China-Fippa, etc, are far more an indictment of an opportunist. Nowadays, a vote for the NDP is like voting for Pierre's or Lester's Liberals, that's the new reality.