I hate to hijack the comments with a response that doesn't address the OPs question at all, but I felt like that wasn't necessarily a fair comparison.
ASP.NET Webforms? Yes, huge mistake you'll regret
ASP.NET MVC? Fantastic choice, you will not regret it so long as you're a microsoft based shop
You can't make a blanket statement like that about ASP.NET, since it's effectively a bifurcated ecosystem at this point (and we're all hoping the WebForms fork dies a quick death).
ASP.NET Webforms? Yes, huge mistake you'll regret
ASP.NET MVC? Fantastic choice, you will not regret it so long as you're a microsoft based shop
You can't make a blanket statement like that about ASP.NET, since it's effectively a bifurcated ecosystem at this point (and we're all hoping the WebForms fork dies a quick death).