The last Leger Marketing poll was done in February, with a much smaller sample size (360):
Two possible factors for the flip between the federalist parties- the negative press surrounding the Quebec wing of the federal Liberals and the recent sponsorship arrest. That said, this latest poll puts Liberal support exactly where it was in the 2006 election, so it isn't a hopeless result.
The last CROP Quebec poll showed a dead heat between the Cons and Bloc, but since then all other polls haven't replicated this result. Leger comes close, and the large sample lends credibility to the results. I'm still somewhat tentative, because if you look at the Leger results for the past year, you see support wavering back and forth between the Libs and Cons, Bloc fairly stable. That tells me, there is plenty of fluidity, soft support that could move in an election campaign. That sentiment doesn't translate to no appreciation of the challenges the Liberal brand faces in Quebec.
On the sovereignty front, only 31% of Quebecers support independence. Even more surprising, amongst PQ supporters 45% think the party should seek to improve the position of Quebec within Canada, 50% think the party should persue independence. I saw a scenario where Harper uses this type of sentiment to argue his approach to federalism has been successful, the need for the Bloc less persuasive.