from Shawn Wildermuth 
If you’re building Internet applications, you’ve probably been bombarded with lots of new technologies the last few years: Silverlight, Flex, ASP.NET MVC, jQuery, etc. While all of these technologies have their use-cases, many of them are pointing to something that is new and important.
The central idea of separating concerns is not new. Back in SmallTalk when Model-View-Controller was born, the benefits of isolating layers of an application were pretty apparent. The problem was that it wasn’t easy to implement. The problem with implementation was never the code…or was exactly the code. The problem is that when you are working on a problem in the user interface, it is far to easy to try and solve it directly in the code. Its not laziness or lack of talent. Its simply a matter of focus sometimes. Under the timeline gun its easy to be miopic about a problem. Its simply too easy to just try and solve a problem by writing code in the user interface (or the View).
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