You had a good G8 summit - until your closing press conference, that is. And, the way these things work, it's the misfired pot-shot at Michael Ignatieff that many Canadians will be talking about this weekend and will long remember.
In your position, you cannot afford sloppy staff work. Precipitate action would amplify the gaffe. But a new press secretary in the PMO when Parliament reconvenes in September would certainly be in order.