Joomla 3.1 will be released around April 15th, 2013. Don't worry though, because it's a one-click upgrade and will be backward compatible. If you’re on Joomla 3.0, you will need to upgrade to 3.1 at that time using the one-click upgrader. If you’re still on Joomla 2.5, you can continue to wait until Joomla 3.5 and still get a direct upgrade.
Joomla 3.1 has been released and is now available for downloading here!