Thunderbolt is actually based on the Mini DisplayPort specification. If anything, Apple will add this to the iPad, but it will look quite different than USB.
The next iPad, rumored for September of this year, is more likely to include major new features, including a higher-resolution display and more connectivity (i.e. Thunderbolt).
The next iPad, rumored for September of this year, is more likely to include major new features, including a higher-resolution display and more connectivity (i.e. Thunderbolt).