a) They didn't open part two with Jonathan Frakes doing the 'Where No One...' speech. Ok, Picard was going to be back next week, but you don't need to tell us that!
That would imply Picard was replaceable... and Patrick Stewart was and is the biggest asset of TNG -- it would have undermined him on a story and marketing level.
But with this episode, let's not forget the dramatic end music! Which was used in a Family Guy cliffhanger to great effect too.