Duceppe asked Landry to stay on as leader. Thprise thprise.
On the other hand, Duceppe could probably bow out as Bloc leader and the party would do just as well without him. He was very good in the debates, but he is fundamentally a very cool and not too congenial guy. The Bloc could probably muster up as much charisma in another leader, so Gilles could push up his time-table to take the helm of the PQ.

I wonder, though, if it's as simple as all that. The PQ has a sovereigntist bent, yes, but it is fundamentally a very conservative party (as opposed to the contrary, a sovereigntist party with a conservative leaning). Gilles is a former marxist. The platform of the Bloc is just slightly to the left of the NDP. Is he really such a shoo-in for the PQ leadership? Bear in mind that the internal machinations of political parties are independent, and often opposed to, what makes the most electoral sense. ie, just because Gilles could sweep to power as PQ leader and win a referendum, that doesn't mean he can win the PQ leadership.