Bus service to the parks in the morning varies from the bus service back to the resorts from the parks. As posted by others, return buses may go to Swan, Dolphin, YC, BC/BCV, and then BW. Even some of these buses will make a direct run at certain times of day, like mid-morning when more visitors are heading to the MK or AK than returning. I think this is somewhat unpredictable.
Bus service to the MK and AK in the morning from the BW is frequently on a bus that makes no other pick-ups. WDW transportation uses a bus dispatch system with CMs at the bus stops using communications systems to notify the dispatcher of the need for another bus. The CMs monitor where waiting guests are heading and request additional buses as needed. The parking lot at MGM is the holding area, so a dispatched bus gets over to the BW very quickly to do a pick-up. There has been a lot of discussion of the bus dispatch system on the Transportation Board here on the DIS with input from Tyler (posting as Chip and Dale Express) who is a bus driving CM. Over the last year and a half (four visits to WDW including two in June when things are somewhat busier), we have seldom waited more than 10 minutes for a bus to either MK or AK in the morning. There have been reports of frustrating breakdowns in the system from time-to-time, but we have found it be generally reliable and efficient.
I always walk to MGM and Epcot, since this is generally at least as fast as taking a boat.
Ralph
