AJAX Toolkit for ASp.net MVC
Since MVC does not have a ViewState or Web Forms feedback model, AjaxControlToolkit will not work with it.
There is a project for this ( http://mvccontroltoolkit.codeplex.com/ ) but it hasn't been released yet.
There are numerous blogs that have different controls, but honestly, I suggest looking at jQuery and its plugins ( http://www.jqueryui.com/ ). MVC gives them a much more natural feel, it is not based on governance.
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Here's another resource talking about it: http://www.hanselman.com/blog/ASPNETMVCPreview4UsingAjaxAndAjaxForm.aspx
Plus, ASP.NET MVC lends itself easily to creating your own awesome ajax controls, especially when combined with jQuery.
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The emphasis in ASP.NET MVC relies more heavily on HTML and client-side code when it comes to user controls similar to the one found in the AJAX Toolkit - you might like the excellent http://www.jqueryui.com/ for some good elements client-side management.
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