At the risk of going off on a tangent, I'd recommend Axe/WatiN. Axe allows tests to be written in Excel by 'Manual' Testers with no knowledge of the underlying test 'language'. It does need a 'Technician' to write the bespoke actions (IE. Today I had to do a slightly complex Table lookup & cross-reference) but once written the actions can be used in tests by the non-techy testers.
I also heard that the UK Government Gateway project (which I believe has 6K+ tests automated tests) recently ported all their tests from Axe/Winrunner to Axe/Watin within a week!! And many of the tests are pretty complex - I know as I worked on it a few years ago...
I'm looking at Selenium at the moment, as a potential Client uses it. But i do suggest a wee look at Axe as a layer above the 'work horse' tool.
