I just read this post by Paul Gielens (http://weblogs.asp.net/pgielens/archive/2009/05/06/why-asp-net-mvc.aspx) about why a group of developers decided to use ASP.NET MVC.
The answer to the question “what made you guys decide to use MVC for this applications” was interesting “because we wanted to learn something new, and because it’s cool!”.
So the feedback on this post ranges from “ahumpff” to “these guys should not be experimenting when someone else is footing the bill”.
I’d just like to pitch in:
a) It’s great to see people showing interest in new technologies. I’d rather have some folks on my team who are eager to dive into a new technology than those who shy away from anything new.
b) There is not a lot of additional info: but assuming that the project was not a multi-million dollar project and there was some room for a little risk. Then “why not?”. In my experience you can play with any technology, but you won’t truly learn it until you have a serious goal. Without a fixed goal you won’t find the pain points of the technology.
c) I believe in risk driven project management. I’m not sure whether it is an official approach to project management. But I like to list all known risks, then decide whether something needs to be done to mitigate the risk. If the cost of mitigation outweighs the risk, then agree to do nothing. In essence, just about everything in PM is about risk management. Anyway, back to the new technology: do an assessment: will this new technology cost me more time to develop this app? Yes/no? No, then use it. Yes? How much? Can we afford to spend X hours on learning? Will it make my team happy? Happy coders write more code… aw heck, let them use it 
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