At times I’ve been CalDAV’s biggest fan. A calendaring protocol which finally stopped actively pretending the Web didn’t exist (I’m looking at you IETF CalSch WG)! But it does seem like its been a hard slog to implement. Keeping my fingers crossed for the future.
(pointed out to me that merely because I found out about Zimbra’s CalDAV support last week at OSCON, doesn’t mean it hasn’t been available since January, mea culpa)