Investigate IObservable<T> for API

[CaptainCodeman]

I think this would add to the .NET-ness of the project and make consuming things easier.

It already has an API around subscribing and would fit perfectly into an app.

See:
http://msdn.microsoft.com/en-us/library/ee850490.aspx
http://msdn.microsoft.com/en-us/library/dd990377.aspx
http://blog.rjcox.co.uk/2010/01/10/iobservable-req/