1 – Testability. No – not talking about the TDD variety, just testing in general. If you’re “not a testing person” that’s OK – the rest of the computer science world has embraced the idea that “testing what we build is a pretty good idea”. You don’t really want your clients to catch that silly “InvalidCastException” do ya? There’s LOTS of reasons to want to test – again not TDD – just good old Unit Testing! It’s easy peasy with MVC and this alone should pull you in to at least check it out – along with why testing can save you time and money.
2 – Control over HTML. I’m sure you’ve heard this before – mangled ID’s, non-validating HTML, etc. Why is this important? Because you might want to use client-side programming for something! I won’t bang this gong for too long – but it’s a lot more than “making ViewSource look pretty” – you’re communicating with super-finicky creatures (browsers) that love to argue – being able to smith the markup experience makes you a more valuable developer!
3 – Extensibility. Literally every part of MVC Is pluggable – and in the last 3 apps I wrote (Storefront, Nerddinner, and SubSonic’s MVC Starter) I used my own ViewEngine to save some time and work. I’ve spun up my own ControllerFactory so I can use IoC (which is awesome fun!) Understanding this is the keys to the kingdom for any developer! Have you ever been freaked out because you needed to use Page_PreRender to get something to load into the ControlTree properly so it will show when you need it to? MVC does not lock you into anything – you’re free to do what you want to.