.NET/Mono Install Base

Question

Me and some friends are considering writing a new FOSS project, and the debate is divided between using .NET or something else.

So I am wondering if there is an advertis

Answer 1

All computers running Vista will have at least .NET 2 installed, and Windows-7 .NET 3.5.1.

Aaron Stebner has a page detailing which version of Windows has which version of .NET installed as standard. So if you know the OS being run by your target audience you'll be able to work out whether they'll have .NET installed and which version.