But Smith said Update Panel is an included feature. "We have no reliability issues in our Update Panel, and if there are issues discovered, we offer full technical support," said Smith.

Even though it had not been available in a general-release format, ASP.Net AJAX ranked high with Adobe Flex in an Evans Data report detailed Tuesday entitled "Scripting Languages -- Developers Choice Report." Flex scored slightly higher than Microsoft's technology.

An Evans Data analyst on Tuesday cited the importance of Microsoft's entrant in the AJAX arena.

"It is a very important technology to the scripting landscape, especially to those developers who favor Microsoft products and Microsoft strategies," said analyst John Andrews, president of Evans Data.

Also in the AJAX realm, an early version of 'jaks, an open-source project combining the Echo2 AJAX windowing system with Tcl (Tool Command Language), has been released, said the developer of the technology, Tom Poindexter.