For a while now I've held off on fully utilizing the MS AJAX framework in the core of mojoPortal because it was not yet supported in Mono but recently, at least in Mono built from svn head quite a bit of the System.Web.Extensions stuff is working. In the past I had an AJAX Extensions pak which could be used to add MS AJAX support for Windows in case developers wanted to use it in their custom features. It also allowed for making the WebPart drag and drop work in Firefox by using the Microsoft.Web.Preview namespace. The Microsoft.Web.Preview stuff is not working in Mono yet but since WebParts are also not working in Mono yet its not needed. However in svn trunk I've modified (or will have soon, merge is in process) the Solution so that these things are referenced and no extension pak is needed. Since some web.config settings are needed to use these things I made a custom Web.config for mono that comments out these things otherwise errors happen on Mono. So heads up to any Mono users who are working with mojoPortal from svn.
If you are working with Mono compiled yourself from svn, you'll need to replace the Web.config file in the Web folder with the one from the _mono_errata folder
If you are working with Mono 1.2.4 or 1.2.5 release versions you will need to either just use the current zip download or use svn/branches/188.8.131.52 because the System.Web.Extensions stuff is not yet available in these versions.
One of the changes to add more general support for MS AJAX was to add the ScriptManager to the layout.master file of each skin so if you are using a custom skin you will need to copy this from one of the included skins into your custom skin.
I may go ahead and make another release with this soon as I know some developers are anxious to start using MS AJAX in mojoPortal and this will make it easier. I used the UpdatePanel in the BlogEdit.aspx page so Categories can be added to a post nice and smooth with no full postback.
Another thing I did recently that is in svn is I implemented a ProviderModel pattern for the IndexBuilders used to build the Lucene.NET seach engine index. This will make it much easier for developers to make their own features participate in Search by implementing an IndexBuilderProvider (which only requires implementing 2 methods). I plan to write a tutorial on that soon but I think most developers could figure it out just by looking at the included providers for existing features.
I'm still a fan of some of the other AJAX frameworks included with mojoPortal, especially dojo which I plan to use more of but its nice to finally be able to use the MS AJAX stuff. UpdatePanel makes things very easy.