NewsGator has released a new beta version that makes use of AJAX to speed things up a bit. For example, when you click on the settings tabs in Newsgator Classic, you're directed to a new page. In Newsgator Beta a window pops up on your screen and disappears when you click close. The page doesn't need to refresh every time you switch feeds or mark items read.
But Newsgator still takes longer to load feeds than Google Reader. And I've grown rather fond of my river of news. Otherwise, the new beta looks and behaves remarkably like Newsgator Classic. While this is great if you've been using Newsgator for a while, it doesn't seem to offer many new compelling features that would convince me to switch back.