this is a very early beta, so unless you're happier without your msn, yahoo, facebook, gtalk etc, you can carry on with an upgrade. however.. some people have no qualms with the OS 5.0. because i use facebook, msn, viigo, gtalk, i don't want to upgrade just yet. i'll wait for a more solid beta (if there is such a thing) or an official release.
If you're having so many problems, might i say you should downgrade back to whichever 4.6 version you were using? I am on 4.6.0.237, which i have found to be rock solid.