The update process is very simple, and complete instructions are available here. Note that there are now easier and better ways of updating than copying the files with FTP.
View more here:
Our plan for Joomla! 3.1 update:
Following up with Joomla! 3.1 release, we will update extensions and template to compatible with this version very soon.
Stay tuned for our upcoming announcements on our future updates incorporating Joomla! 3.1. But remember, if you are building a website Joomla 2.5 is the way to go, Joomla 3.x series are short term releases.