If you don't see intellisense for your cascading style sheets in Visual Studio 2008 or if the CSS intellisense seems to have dissappeared or just stopped working here's how to get it back:
For CSS intellisense to work in Visual Studio 2008 the CSS text editor options area has to have its tabs indenting setting set to "Smart".
To change this setting use the menu to navigate to: Tools - Options.
In the options window expand the Text Editor - CSS nodes (if you don't see them check the "Show all settings" checkbox in the bottom left corner").
Within the CSS node select "Tabs" and then set the Indenting to "Smart".
Refer to the screenshot above for the proper setting.
With this setting corrected you should now have CSS Intellisense in Visual Studio 2008 working again.