No public betas are very much not, i have comm and am using the public beta, private betas are for pro users or users that conitec has approved to use them.
heres the public beta, I believe its 7.77:

http://www.opserver.de/ubb7/ubbthreads.php?ubb=showflat&Number=263522#Post263522

EDIT: oh, looks like its released already. I guess 7.78 isnt public beta yet.