The myTouch 3G has a highly capable browser that I found to be much snappier than that of the G1. T-Mobile's 3G network is speedy (where available) and the myTouch 3G's browser renders Web pages quickly.
Perhaps the biggest improvement is that the browser now supports multiple windows. This means you can have several Web sites open at a time and jump back and forth among them with relative ease. There is a floating menu bar that will appear or disappear at will, and it lets users navigate the Web and otherwise control how the browser functions. Full HTML isn't a problem for the browser, though full support for embedded video is still lacking.
Google's own services, such as Maps, run very well on the myTouch 3G. I found Google Maps for Mobile to be extremely robust, and it offers nearly as much functionality as the desktop version. Paired with the myTouch 3G's onboard GPS, and I'd say most people could forgo a stand-alone GPS unit. My favorite features are the way Street Views works and how maps and directions can be sent to others. I also tested Google's Latitude location-sharing service. It works OK, but not perfectly. I have to wonder why Maps for Mobile can pinpoint me down to the meter, but Latitude often gets the town wrong.
The Android Market application store continues to grow. Thousands of applications are now available for the Android platform, and this is certainly one of the myTouch 3G's strengths.
Perhaps what most sets the myTouch 3G apart from the G1 is that it comes with the ability to grab T-Mobile's Apps Pack. The Apps Pack is an application from the Android Market that learns user behavior and will suggest other applications and/or services from time to time.
The Sherpa application is also on board. This application can be very useful in helping people find and locate local resources, points of interest, and other attractions. Users can also set preferences so if you perform a search for "coffee shop," it will know that you prefer Dunkin Donuts over Starbucks (or whatever your favorite coffee store is).
The myTouch is a handsome device that offers plenty of power to the connected user. Media features may be lacking compared to the competition, but tight integration with Google services and the Web make it a solid pick for those who live more of their life online than off.
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For Further Reading
The G1 Wows Consumers, But Enterprises Must Wait (registration required)