interesting topic... if you are interested in the next big things of the future (not only related to porn), take a look at
http://www.iftf.org/features/reports.html (institute for the future). I think that the 2 next big things, which are pretty much interrelated are :
1) GPS technologies ... soon, every cellphone will come with an integrated GPS
2) Context-aware gaming: computer games will be partially virtual and partially real. The context will be real (environement and other players), but the interactions will be virtual. Gamers will have special glasses that will incorporate virtual elements. Think of a real life pac man game hahaha
Both of those 2 technologies might have interesting applications to porn, but can't really find any right now.
Maybe it could be a cool thing to have an adult social networking site that uses GPS technology or GPS ad targeting. i.e When you surf the web with your cell phone, advertisements would be related to your location on earth. Let's say you're on corner of street X and street Y... you would see some McDo ads which is located at 10 meters of you... etc.