The Liberal leader invites your questions.
Michael Ignatieff tried something like this in the fall of 2010—see here and here for examples. I don’t recall whether Mr. Ignatieff actively solicited questions as Mr. Trudeau is doing now, but (as Susan Delacourt notes as well), during its earliest days in the House, the Reform party had phone and fax lines through which constituents could submit questions that would be asked in the House (note the Speaker’s concern about that gambit).
During the last election, the Liberals promised that, if elected, they would create a “People’s Question Period,” during which the Prime Minister and various cabinet ministers would take questions from the public.