After the closure of the hosted Feed2JS site http://feed2js.org/, future traffic will be sent here as an informational site. Here you will find alternatives for Feed2JS as well as details for hosting the service for your own site.
Many site may not get the information in time, but all that will happen is that the feed content will be skipped, e.g. leaving a blank spot. If this is a sidebar on your site, the impact will be none. If you rely on the service, well, there will be a gaping hole.
I tested this by creating a simple page with a Feed in it, and changed the URL of the calling PHP script so it would return a error message from the serber, and skipping the feed attempt. On a normal Feed2JS attempt, this would just leave a blank spot.
Related news will be posted here.. if there is anything.