2.2. RFC 2445bis
http://www.ietf.org/internet-drafts/draft-ietf-calsifyrfc2445bis-00.txt
Changes done so far mostly clerical to make document more readable
http://www.calconnect.org/publications/icalendarrecurrenceproblemsandrecommendationsv1.0.pdf
Are there issues related to sync that should be considered?
What needs to get done for implementers to jump from vCal?