Although a lot of code has changed and been added from beta9 it's had a lot of testing. Probably more testing than any dhcpcd release to date. You now have the aforementioned link carrier detection which is needed for dhcpcd to fully pass Apples Bonjour Conformance Test suite. Well, the IPv4LL section anyway as it's the only part that applies.
Props for this release go to Michael Durrant of Arcturus Networks for fully testing dhcpcd for IPv4LL compliance (as it requires OSX to run the test tool, which I don't have) and generally finding little "corner cases" which break things.