I just finished watching 1 hour worth of video on Google Dart. To put it simply, Dart tries to introduce a new browser based, client-side script language which let us not have to deal with Javascript : kinda like CoffeeScript.

A few things that I find intriguing:

1. C style syntax : Google consciously don't try to invent new syntax and stick to the syntax that most dev already familiar with.
2. Optional static typing : specifying a type against parameter or variables are optional and mainly for development time checking (intellisense & warnings). On ‘production mode’, Dart doesn't enforce it.
3. Dart is designed for dev to work with an ‘offline first’ approach. The server component will be simple REST component like WCF Data Services, Web API, or NodeJS type of service (which to note; all the above will run on Azure)
4. View engines work very similarly to XAML. Google is still brewing the view engine and seems to borrow a lot of the concept from XAML & its view model binding capabilities.
   The view engine will be based on using HTML as a templating system, which will get parsed and output javascript code that generates the DOM elements. It'll have capabilities to bind visual elements to observables.
5. Just like CoffeeScript : using Dart would mean that we as the developer will need to debug on code that the framework generates. There's no correlation engine as yet between the source code and generated code.