He may be targeting Windows users (since there are an awful lot of them), or want to tie in to some Windows-specific functionality, or a host of other reasons.

He may be targeting Windows users (since there are an awful lot of them), or want to tie in to some Windows-specific functionality, or a host of other reasons. Of course, JRuby on Rails (Rails on the JVM) is also a very viable option, and comes with a few nice features you don't get in Rails (Job scheduling with Quartz being my favorite), at the cost of having to deal with the complexity of the JVM (GC tuning is a pain in the ass). The framework and language you chose are only a part of your company strategy.