Back around the 02 timeline while I was elite on NW I can recall a few flights with the captain coming out and being somewhat sociable before takeoff. Not just addressing FC and thanking, but talking to passengers boarding, and at least in once case noticing a young PAX (first time flying) and personally bringing him a pair of wings after boarding was complete.

Since I've been doing the weekly shots for the past couple of months, no appearances from the captains period.