<p>I've just created my first Preview 5 error and it doesn't seem to place nice with Resharper.  All the C# in the Views are coming up with errors, things like &lt;%= Html.Password("currentPassword") %> has the "currentPassword" highlighted with the following error: Argument type "System.String" is not assignable parameter type "string".  </p>

<p>IList errors = ViewData["errors"] as IList; has the IList highlighted as "Can not resole symbol 'string'"</p>

<p>Has anyone seen this?</p>

Did you try
latest nightly build
of ReSharper 4.1? In some cases the bug in 4.1 manifests itself with numerous ambiguity errors, and it has been fixed within the follow up build.