The prototype described in this blog became real. Take a look at http://rapmobile.eclipsesource.com for more infromation.
The result is just awesome. You can write your UI completely with SWT on the server side and access it with the iPad/iPhone/iPod or with just a webkit based browser. The UI experience feels just like native Cocoa Touch. Eclipse RAP and the RAP protocol makes it possible ;). Please note that this is just a prototype and not yet available for download. But you can check out the RAP protocol using git and develop your own client representation.