Hi,
I'm not sure how soon I will get to it but once I have some initial work done, I'd be glad to have your help testing it. I will look into vCalendar as well. We do already support hCalendar microformat in Event Calendar Pro.
It is very difficult for me to estimate when things will be completed, I can usually estimate to some degree how much effort will be involved but the problem is that other things need to be done as well so I don't usually get to just stay focused on one thing at a time. I'd guess I need about a solid week of effort to implement iCalendar but it may take a month or so to actually apply that amount of effort.
I would like to implement both import and export as iCalendar, the export probably will be a link similar to RSS for a list of events but also it should be possible to export a single event.
Best,
Joe