The Nokia 710 might have a bit lower parameters than its bigger brother, the Lumia 800, but it is definitely the device that can be customized to your personal taste thanks to the interchangeable back covers. Currently we are sure that they come in white, yellow and magenta, but there are probably blue and black available too. Besides that, you can also purchase cases for the 710.
As you know the 710 shares the design of Nokia 603 so their cases are pretty much the same, however, the 710’s case has an opening for the LED flash. Other than that the 710 is a bit bigger than the 603 so you can’t really use a case meant for the 603 with your brand new Nokia 710.