I think we'll see more and more electric motorcycles in the future. Currently they have pretty limited range. Everyone already knows that though, and you can either live with that, or you can't.
I think the energy density issue will be solved though, and when that happens they'll (obviously) become more popular. Don't get me wrong, I love internal combustion engines, but I'd love to see a city that was quite and filled with fresh tasting air.
2012 Yamaha WR250R