Beta releases are not upgradable to full releases unfortunately so it
will be a clean install - has always been the way and given the nature
of beta releases it always will be ! Beta versions are for bug finding
and not meant for serious use.

If an OS has a Release Candidate then these generally are feature
complete and the standard updates will make them equivalent of full
releases when they go live, even though they'll always report as being
Release Candidates.

You do not have to upgrade from the beta. Just update and upgrade the
packages. If you feel adventurous or want a fresh start, then start by
backing up your data.

You can try the dist-upgrade if you want. Or you can make a bootable disk or
usb key from a newly downloaded ISO of the final 11.10 release. When you
reboot the computer with the disk in or usb inserted (make sure your BIOS
supports this) it will detect your previously installed Ubuntu and offer to
upgrade. Always backup even for an upgrade. Strange things can happen at the
most inconvenient time, even though Canonical says upgrades are safe.
However, after going to all of this trouble you are no better off than just
upgrading packages. The only way to make a fresh start in my experience is
to do a clean installation.