The features are a light weight body 3.8oz/106g ,
256MB on board memory and 256MB flash,
a crisp High-resolution 320x240 pixel color display
talk time of Up to 4.5 hours
Where it differs from the Tour released last week on Verizon & Sprint is it has no trackball, lighter and has WiFi... Though the Tour has a better display High-resolution HVGA 480x360 pixel color display
Some Twit terachi folks believe the blackberry Gemini has a chance "@animalsteele: New Blackberry Curve 8520 $48.88 and It's FIRE; No trackball" @AnimalSteele is a hiphop taste maker and is behind the success of some of the industry's best. But will he be right about the T-mobile's new Blackberry Sidekick?
more info here: http://www.engadget.com/2009/08/04/t-mobiles-blackberry-curve-8520-unboxed-and-handled-with-video/
See the unboxing for the video here: