I use "integrate_views" to combine controller and view specs. The thing I discovered just now is that if you have nested describes, you have to place "integrate_views" inside the inner describe or "have_tag" won't work.
The error you typically get otherwise (even when the element exists) is:
Expected at least 1 element matching "div#content", found 0.
For this particular project I'm using RSpec 1.1.3.