Quite exciting new features of Nessus 5.2, such as including screenshots in the reports(as example if RDP port was open - screen of RDP login), full IPv6 support and other...
Nice looking HTML5 interface, flash also available if you miss it.
"With the release of Nessus 5, all Nessus server configuration is managed via the GUI. The nessusd.conf file is deprecated. In addition, proxy settings, subscription feed registration, and offline updates are managed via the GUI" :(
To set update of plugins to everyday as example, go to Configuration - Advanced - verify auto_update - yes and auto_update_delay - 24 (this are the hours). This way it seems there is no need to cron anything. Anyway you can start update manually via GUI or by the script (FreeBSD example: /usr/local/nessus/sbin/nessus-update-plugins )