Amazon Silk, as described by Amazon:

Today in New York, Amazon introduced Silk, an all-new web browser powered by Amazon Web Services (AWS) and available exclusively on the just announced Kindle Fire.  You might be asking, “A browser?  Do we really need another one?”  As you’ll see in the video below, Silk isn’t just another browser.  We sought from the start to tap into the power and capabilities of the AWS infrastructure to overcome the limitations of typical mobile browsers.  Instead of a device-siloed software application, Amazon Silk deploys a split-architecture.  All of the browser subsystems are present on your Kindle Fire as well as on the AWS cloud computing platform.  Each time you load a web page, Silk makes a dynamic decision about which of these subsystems will run locally and which will execute remotely.  In short, Amazon Silk extends the boundaries of the browser, coupling the capabilities and interactivity of your local device with the massive computing power, memory, and network connectivity of our cloud.

Here is Amazon's video on the new Silk browser: