I released a commercial .NET app 2 weeks after the official 1.0 release and am still using the framework. I've dabbled in Ruby, Java, JS, written an iPad application, etc. I have my gripes with some of the .NET tools but I really like C# as a language. My biggest gripe is the business decisions made by Microsoft over the past few years. Under Gates, Microsoft really understood the developers created their monopoly. Under Balmer it feels like Microsoft wants to extract every ounce of blood from developers which is ultimately going to bring down the house.