What is the best and cleanest way to implement A-B testing in asp.net mvc? That is, when we make new changes to an asp.net mvc web site, we want to test the new html/css/js with a certain subset of visitors (defined on cookie, login id, etc) and then analyze some metrics (page response time, number of pages visited, $$$ in sales, etc) afterwards to measure the level of success of the changes.
I am looking for a clean way to implement a way of choosing what view (html/css/js, etc...) to render using asp.net mvc.
Check out FairlyCertain (http://www.fairtutor.com/fairlycertain/) when you get a chance. It's a .NET A/B library that you can pretty much just drop into your project and start writing tests.
Unlike the Javascript libraries from Google and VisualWebsiteOptimizer, everything happens on the server so you don't suffer any performance, user experience or SEO issues. I've been using it in my stuff for a while now and it works quite well.