We recently completed a two-part post on managing your Explorer cache. In Part I we noted how the content available at the ArcGIS Explorer Resource Center is delivered via ArcGIS Online. We also talked about the fact that ArcGIS Online content is updated often, and explained how to manage and refresh your cache to ensure that you're always looking at the most recent content.

If want to know when ArcGIS Online content is updated, there's an easy way to do so.  The ArcGIS Online Blog provides information about all changes and updates, and includes RSS feeds to which you can subscribe. We'll also keep you posted here.