Say I would like to follow the events of my local art gallery and the local gigs of a certain musician. The gallery and musician could put out a feed which I could follow, with values including date-time, address, info-url, ticket-url, details. My event-feed reader would pull in the gallery's and musician's events from their website, and populate a calendar with them. Moreover, I could set the reader to only display events in the region I care about, so the only gigs of the musician that would appear would be the ones when they come to my town.
They seems a simple, decentralised way of following events, but I'm surprised nothing like this already exists?
https://gist.github.com/erkattak/071ab8af1fc64013d955
xCal: iCal and XML together.
Unfortunately, it is not popular at all.
Google Calendar for example will let you follow published external calendars by URL: https://calendar.google.com/calendar/u/0/r/settings/addbyurl.
So yes, the technology base exists. There's other active uses of it here and there, e.g. many services send event emails with ics files attached, containing a single-event calendar that some mail clients (including gmail) will show/import automatically.
To date it hasn't really become popular as an RSS-style tool though - from what I've seen it's largely used directly within your own calendar, rather than as a browseable list of upcoming events from many sources.