Reading the MSDN documentation in a web browser is a real pain because the absence of syntax highlighting. In those web pages, code spinets are surrounded by a div with class="codeSnippetContainerCode".
I came across Sight, a chrome plugin. If you open a .js file it would show the syntax right. But it wont syntax highlight source code embedded in a page.
EDIT
Looks like lifehacker
has a good solution with Code Highlight chrome plugin.
