I fired up the App Store on my iPhone and I saw Carcassonne at the top of the list. Not only does this game look beautiful, but it plays great, AND has multiplayer! MUCH more than can be said about the Catan game (phooey!). Additionally, according to the App Store page, if you buy the app now for $4.99, you’ll get the iPad upgrade free when it comes out (instead of paying the full $9.99).
Get it now! Carcassonne for iPhone
If you’re into euro games, you may also be into these iPhone/iPad games as well: