The guys at Particletree published a really cool article on what technology is behind four popular web applications. While the applications are different in functionality, what really astounded me was time to market and its corresondance with technology platforms. Of all four applications, Blinksale took a short three months to build out. The .NET platform RegOnline took three years - approximately 30,000 lines of ruby code to 400,000 lines of C#! (Can Visual Studio even handle a library that big? :-) ) Here's the real kicker: RegOnline makes 10 times more per customer, but employs 10 times more employees and fields 20 times more support requests.
Now obviously there's many unreflected variables in all of this, but the statistics really say a lot. If I had to choose, I would definitely choose to stay lean, mean, and of course...on a Ruby on Rails platform. How much has the web changed in the last five years? I believe you've got to contain and focus your app so that you can change with the needs of your customer.
Who do you think has the best situation here?