The latter brings new additions, such an improved overall interface, an LP feature, a Genius Mix functionality, and oh, hey guess what? It also breaks the ability for the Palm Pre to sync with iTunes. This doesn't come as much as a surprise as Apple and Palm have been going back and forth on this issue. While mildly entertaining at first, this little cat fight is beginning to wear thin, particularly for Pre owners, we suspect.
We'll have to wait and see if Palm fights back and some think that the company might try to sneak a fix into the widely reported but unreleased WebOS 1.2 update. Of course, you can always choose not to update to iTunes 9 or use third-party software to sync your device with iTunes.