Agree that the celebration in WDW is being touted differently -- but I'm surprised to hear that it wasn't very visible. We were there a year ago and reminders of "Happiest Celebration on Earth" was EVERYWHERE. Maybe it was because the new/borrowed attractions for the celebration had just opened then? I'd imagine they're not going to focus so heavily on it now and will want to start to promote the new theme more heavily as the 50th winds down.
BTW, we've been to WDW each of the last 3 years and attendance has been way up each time, from our observations. There's been a steady climb since people have gotten over post 9-11 fears about travel -- and since WDW has been offering promotions like free dining. Disney has pumped a LOT of money into marketing the Florida parks, we see it constantly here on the east coast.