ISPconfig will be very good solution for hosting when release some features like: dovecot, bind, mod_chroot, traffic quota, disk/bandwidth stats... supports. For 2010 can be the best secure controlpanel.
BUT ISPconfig needs other very important thing, it's a billing system. I think the best is whcms:
But whcms doesn't have ispconfig support. I was searching information and i only found it:
We have 2 options:
1. Try to speak with whcms staff. They should win costumers adding ispconfig support.
2. You can post here other billing systems compatible for ispconfig 3, if you known it.