Here's my list of feeds that I review daily. Some offer more than just Ajax-related content but I read these mainly for the Ajax material.
http://jquery.com/blog/feed/ http://ajaxian.com/index.xml http://www.dzone.com/feed/frontpage/ajax/rss.xml http://blogs.pathf.com/agileajax/rss.xml http://ajax.phpmagazine.net/atom.xml http://feeds.feedburner.com/encytemedia http://www.jackslocum.com/yui/feed/atom/ http://feeds.yuiblog.com/YahooUserInterfaceBlog http://feeds.feedburner.com/miraculous http://www.ajaxmatters.com/blog/feed/ http://www.learningjquery.com/feed/ http://remysharp.com/feed/atom/ http://trainofthoughts.org/blog/feed/ http://www.danwebb.net/feed/atom.xml Enjoy. Rey