funny you should ask, I was just thinking about this last night
Yes, we are definitely planning on offering REST interfaces to access the store (in adddition to our existing SOAP/JSON interface).
I'm working on adding some really simple GET apis to do things like a request a calendar folder as a .ics/.rss/.atom/.xml/.html content, or a contact folder as .csv/.vcard/.xml, etc. Initially this will be for user's to access their own content, and then shortly after it will be expanded to access other user's contet and allow people to publish things like calendars, contacts, etc.
roland