I haven't seen any screen shots of OS2008, but theres enough photos floating around to get an idea of what the new theme is like. For example, take a look at atmasphere's photo or the Nokia press photos.

What does everybody think of the new default theme? So far, I like the transparency and the new status indicator icons, but I'm not real crazy about the task navigator icons (Internet, Contacts, and Applications). I like the new icons better than the OS2007 ones, but they seem a little cartoony and WinXP-like for me.

I'm looking forward to creating some new themes for OS2008. I started making some for OS2007 but I decided to wait for OS2008 to come out before I release anything. I was very excited to see in the manual (posted on the FCC site) that the items in the task navigator will be customizable! Check out page 8 of the manual where it says, "The task navigator contains the following items by default. To change the items, tap [application menu icon], and select Settings > Control panel. In Control panel, select Panels."