Intellisense-jquery-mobile is a project mainly written in ..., it's free.
jQuery Mobile data-* attribute Intellisense for Visual Studio 2010 SP1
Originally based on HTML 5 Intellisense for Visual Studio 2010 and 2008 but updated after HTML5 & CSS3 in Visual Studio 2010 SP1, this adds Intellisense support to Visual Studio 2010 for the jQuery Mobile data-* attributes.
To install, copy the html_5_jqm.xsd to the appropriate Visual Studio schema directory (e.g. C:\Program Files (x86)\Microsoft Visual Studio 10.0\Common7\Packages\schemas\html) and execute the corresponding .reg file for your environment.