In the software development world, staying pragmatic is one of the hardest things to achieve. If you look back historically at the IT over the last 50 years or so there's always been two competing factors, Unix or windows, apple or PC, Firefox or Internet Explorer the list goes on.
So over the last couple of months I've looked seriously over changing my development language of choice (C#/.net)(this is something I do every 12/18 months to stay on the ball). Well for the first time since starting .net I came upon a worthy rival in Ruby and probably more importantly Ruby on Rails. In all the emotions of finding a new fun choice, you start to get a bit carried away and start thinking about changing everything especially when Ruby doesn't play too nicely with Windows.
However when you consider the business side of things, I don't believe the productivity improvements of Ruby hold as a big enough argument, as it would take about a year of cross training to Ruby to become as competent a Ruby developer as I am a C# developer. During this cross training process my customers wouldn't be getting the best value for money, so for the moment I'll be staying where I am and taking all the things I've learned from the Ruby world back to .net with me.
Don't take this as Ruby is rubbish, it's just that at this point in time I don't believe there is a valid reason to convert from .net, although I'll be keeping an eye on the language over the coming years just incase that changes.