I\'ve been arguing with some friends on the university, and we can\'t get to a point to which is the framework with more scalability for web applications (and still very fast).<
Web framework scalability is a bit of an over thought question (some would say p155ing contest). Unless you are getting mega bucks (good luck with that these days) and can ensure millions of visitors per day all those frameworks can handle it well (as can ASP.NET).
Personally I would always choose ASP.NET. It is as scalable as anything and has the best developer tools. Only downside is hosting and operating system costs.