Nokia introduces uniquely styled mobile phones in the new Prism collection.

The Nokia Prism phones Nokia stand out with a signature diamond-cut design, featuring sharp angled lines, geometric patterns and graphic light-refracting colors.

I am not sure if Nokia got the inspiration of the diamond-cut design from the Seiko Wired Delta watch collection. At least these watches with the facetted glass design fit perfectly to the Nokia 7900 and 7500 Prism.
The Nokia 7900 Prism is liquorice-black and sports an anodized aluminum backcover, which is coin-stamped and laser-etched in Nokia Prism's signature diamond-cut design. Features include OLED display with 16 million colors, 2MP camera, 1GB memory, Quad Band GSM and animated wallpapers.
You can choose from 49 illumination colors. The chosen color radiates from under the graphic key-mat as well as from the LED display.

The cheaper Nokia 7500 features also a 2MP camera. Other features include microSD card slot and media player.

The two new Nokia mobile phones will be available in the Q3 of 2007 with an estimated retail price of EUR 400 (~$551) for the Nokia 7900 Prism and EUR 210 (~$289) for the Nokia 7500 Prism, before taxes and subsidies.
Via this Nokia press-release. See hi-res photos of the new Prism phones here.