Nikhil has updated his controls for ASP.NET AJAX 1.0. Download here

Quote from his blog (so you know why you should go and download them):

• UpdateHistoryThis is a non-visual control that allows you to add history entries to the browser's navigation stack selectively for some post-backs, and not for some others. This helps fix the back button to make it work, and allows you to implement Ajax patterns such as "logical navigation" and unique URLs.
• StyledUpdatePanel A simple derived UpdatePanel that adds CSS class semantics. A simple addition, but a useful feature, nevertheless, that didn't make the feature cut.
• AnimatedUpdatePanel Another derived UpdatePanel that displays new content using a variety of animations or effects: slides, wipes, cross-fades as well as a visual highlight. This allows you to implement the "visual notification" Ajax patterns such as the one second spotlight and one second mutation.