I think in many ways the solution was already discovered: don't create the expectation that the user will read everything. When they log on, show them the most recent or most significant events, and provide a way to find older events if they want. Twitter, Facebook, plenty of news sites, aggregators like HN & reddit, all hit on more or less this.

Technically, there's no reason it couldn't be done with RSS feeds. But the language of 'subscribing' encouraged thinking about RSS feeds in a different way.