I have Visual Studio 2010 /SP1 / MVC 3 (With April Tools Update) installed on a machine with a fresh install of Windows 7 64-bit Professional.
I do not have resharp
I was experiencing the same issue. It started to happen randomly when I changed the view engine in the Views web.config to a custom one. It is a known problem VS2010 Intellisense has issues with recognizing reserved words when custom view engine is in place or when a view inherits from a custom view page.
Everyone running into Razor Intellisense issues should check this out. None of the above fixes (reinstalling VS, rapplying SP1, reapplying MVC3 Tools Update) did help.