Captain McBain wrote:
At the end of "All Good Things," when Q appeared onboard the Enterprise and spoke to the old version of Picard, do you think Riker and the rest of the crew could see him?
Call me crazy, but I don't remember a scene like that anywhere in the episode. Not where Picard and Q were on the Enterprise talking in a position where others could see them.
It was at the end, when the Enterprise was trying to close the rift. Q appeared next to Picard, and then threw out his famous line: Goodbye, Jean-Luc. I'm going to miss you. But then again, all good things must come to an end.
Or something to that effect.