Mozilla has released a preview to what future Firefox version may look like running on the Android Platform. While you can easily see the new UI changes, it now looks more like a native Android app, there is a lot more going on 'under the hood' in the forth coming version. For example the (current) XML UI Language is being scrapped in place of 'Native Android Code', meaning that pages will load super fast, just like the ICS browser.
However improvements to speed will have repercussions on the functions. One of the main benefits of Firefox is 'Firefox Sync', this will have to be re-written to function with the new code. Likewise, user-created extension will have to be re-written too. This may mean that Firefox for Android will fall slightly behind on its vast feature set. However, I'm sure the team at Mozilla will add the features back in due course.