"It's pretty special to be back on the winners' podium again," Drysdale said.
"I don't think I was at my best, I think there's still more to come, but it was good enough today and we've to go and work now for 10 months away [in London]."
It was Drysdale's fifth world title and an amazing effort considering his injury problems.
Uru and Taylor looked strong but were overtaken by Great Britain's Zac Purchase and Mark Hunter with about 200m to go.
Twigg, in the lightweight single scull, dominated early and led by a boat length at the 1500m mark but faded to finish third behind Mirka Knapkova of the Czech Republic and Ekaterina Karsten of Belarus.
The New Zealand men's coxless four last night added to a long list of Kiwi rowers who have qualified for the London Olympics with a second place in their B Final. Jade Uru, Ben Hammond, James Dallinger and Chris Harris took silver in the B final behind Canada.
A record 12 New Zealand boats have qualified for the Olympics following last night's final session of the championships.