I think the future will be resistive multitouch.
Just because everything can be used to touch the screen and the actual touchscreen resolution is far superior.
If you haven't seen already check out the videos from Stantum. They're doing a AMAZING job. Their resistive multitouchscreens can actually used with a brush! How cool is that?

As some may know, I'm currently building a MultitouchTable. (A video of an early version on my youtube-channel)
There I'm using Infrared emitters and Infrared cameras. These are better on tables, because you can use fiductual markers (something like barcodes) to let the table know what you've putted on the table. For example a glass of wine. The table will now project more information about the wine around the glass.
Sorry for a little bit offtopic...