I missed it, I’d even seen the inimitable Wilfredo on the lists and it went right by me, but I ran into Nat last night at Buzz’s WWDC party, and he rather riveted my attention (as I think he knew he would), that iCalServer announced yesterday? Turns out its an open source CalDav server, written in Python (Twisted), Apache 2.0 license, with great unit test coverage. (which bodes well for the trial by fire known as interop)
update: Um, and how long as Cyrus Daboo been signing his emails “Apple Software Engineer”? Yup, I was asleep.
update 2: wsz confirms trac unhappiness (and my Twisted inside observation), I guess I just got in in time, if you email me, I’ll send you a tarball of the src.