I just upgraded to RC3 on my test site and no problems with install. However with it installed I find I am unable to install K2 and get the following error:
1146 Table 'cdmaste1.tdn_k2_categories' doesn't exist SQL=SHOW FULL COLUMNS FROM `tdn_k2_categories`
I have it on a joomla 3.3.4 site. The new backend has a nice look and feel. Kunena seems to work nicely. Sorry reposting to RC3