A Chinese site IT168.com has recently leaked specifications about Dell's latest XPS Ultrabooks along with some photo snaps
http://www.notebookcheck.net/Dell-XPS-14-and-15-specs-leaked.76809.0.html
I read something else on the on a website which showed pictures of the chinese presentation: XPS 14 will have a i7 U CPU (ULV) and XPS 15 will "only" feature full V CPUs (= 35W). Check it out:
http://dell.benyouhui.it168.com/thread-2224590-1-1.html