1 Question Extensibility Survey

WCF has a whole lot of extensibility points. Many of those extensibility points use
similar systems for describing and installing extensions, but overall you still
end up with multiple ways of doing extensibility depending on what you're
extending.

The Managed
Extensibility Framework
is a standardized plugin model for dynamically
composing applications. If you haven't
heard of MEF before, there's an introduction on the site, a short demo
together with Visual Studio, and a longer explanation. These types of plugin frameworks seem to be
increasingly popular as a way of extending the application development
experience.

Question:

How would you expect a more uniform model for extensibility
to make developing or using WCF applications easier, cheaper, or better?

(There are absolutely no plans at this time for using MEF with
WCF or changing the extensibility model.
I'm just curious what your impressions are.)