I've installed on my test page Joomla 1.7RC1.
When I got to the administration area on Community Builder components go, I get the following error
Fatal error: Call to a member function getCfg() on a non-object in /var/www/web0/html/jom1.6/administrator/components/com_comprofiler/plugin.foundation.php on line 3228
Wanted to encourage this only briefly, so that this can be fixed in the future.
Sorry for the bad English, this has been translated using Google.
We are working on these compatibility issues and hope to have an Release Candidate for Professional members very soon that will work on all Joomla versions - including Joomla 1.7.