Free unlimited installation and compatibility support is available at Microsoft, for Windows Vista, but only for Service Pack 1 (SP1). This support for SP1 is valid until March 18, 2009. Chat and e-mail support is available only in the United States and Canada.
Some issues may require more advanced support for which there is a charge.
By the way, I used the support for Vista via this option, earlier if any thing needed I used to chat directly to product group (using MVP ID) where as this time around I used the public support system as it was quite good enough and really prompt service