A quote from Tim Bray’s review of a prerelease Samsung Galaxy Tab on some of the cool features Samsung added to the Android interface:

You can drag things on and off of the mini-launcher at the bottom of each screen.

There’s a way-cool text-selection control.

The browser has a rotation animation.

The scrolling of the app-tray screens is sideways (who cares) and circular; get to the end and you’re back to the start.

Android OS has been out for two years now and animating a screen rotation is only just making an appearance as an OEM add-on. This is why Apple designs the entire product top to bottom, details like this are just too easy to overlook in open source software. I really don’t think the strategy of letting third parties fill in the rough edges of your operating system (or any product for that matter) is one that leads to a high level of quality.