For the next 10 years or so I'm guessing they'll be trying to make it more fuel efficient, then I'm guessing they'll try to make a fuel efficient super sonic plane, and try to make planes bigger than the Airbus A380, after then, I honestly can't guess, I've heard ideas of them trying to make planes that go into orbit and then back to Earth and can get you from pretty much any place to another extremely quickly, I don't see that in the next 20 years, but you never know!
I see fighter jets going pilotless...I think they have the technology to make them exceed human limitations..both gs and avionics/weapsons....for commercial..I see more fuel effecincy being a big thing