I'm midway through a two-week loan of an iPad. While I'm not likely to buy one based on that week of use, it is a beautiful machine. I've downloaded a page full of apps designed for the iPad, and therein came a surprise. I use the iPhone daily and have a serious app jones there. I assumed that the iPad apps would be just bigger screened versions of the iPhone apps, but in most cases they really are a new experience. The Apple multitouch gestures, which are so essential to the iPhone screen, are very often unnecessary on the iPad, particularly those needed to expand certain portions of the screen for visibility.
The takeaway from this realization is that you wouldn't really need an iPad to take advantage of the great design paradigm of the iPad apps (check out, for example, the NPR iPad app which is much nicer than the iPhone app, and the Evernote app, which is not only nicer to look at but much easier to use than the Evernote apps I use on Windows, Windows Mobile, Mac and iPhone platforms.
So, I'll bet that we see this great application interaction/industrial design spread from the iPad to the desktop. Who says that all desktop apps have to follow the standard File|Edit|View, etc. menus found on Windows and Mac desktop apps today? There's not much in an iPad app that needs to change for the desktop.