When I upgrade to dbus-broker should I expect anything to break?

Archdevs, Just got the announcement about the replacement of dbus-daemon with dbus-broker. The RFC link is rather terse on any problems users may encounter when upgrading. Will all existing rules be accepted by dbus-broker or should we expect custom rules to break? (like custom access to embedded devices as character devices) What has been the experience of the devs in making the change? -- David C. Rankin, J.D.,P.E.