When Facebook’s page sharing feature is used it accesses that shared page to build a little preview for display. It caches that preview and often won’t pick up subsequent changes to that preview data, whether that might be a new image or updated copy. That can be frustrating, especially when a client is hot to push an update.

It turns out you can force Facebook to re-crawl your site and update its cache by putting your URL into this tool: http://developers.facebook.com/tools/lint/. That seems to shake the cache out.