Either DB though the last filler "season" would last for 24 episodes (it usually takes that much for the intro to change) or then they were just joking. I believe it's the latter because there's no way they didn't know about fillers ending after seeing the preview in 220. That and they joke around a lot.
That's an understatement. yhbt, remember: You have been trolled. It's part of their website address even; I remember when they 'dropped' Naruto.
For those whiny people complaining about the nostalgia value: it's a new series, they have to establish a character relationship for those who might have dropped the series or never watched the thing at all. It's common marketing sense.
I wonder, the words they gave through the episode, Shitsupuu, wtf does it mean?