Despite Asian availability for a few weeks now of the 7500 model, it seems Nokia has just today decided to make its so-called “Prism collection” official. Perhaps a great gift for the mathematics professor or physicist in your life, the two span the spectrum of radio coverage and features; the 7500 is naturally the lower-end of the two, featuring a QVGA display, 2 megapixel camera, and data topping out at EDGE speeds. The 7900 adds a fourth band of GSM coverage (Americans may want to stay away from the 7500 thanks to an absence of GSM 850), WCDMA 850 / 2100, 1GB of internal storage, and a trick 2 inch OLED screen. Both phones ride atop Series 40 3rd Edition and should be in shops this quarter — if they aren’t already — for €210 and €400 (about $288 and $549) respectively.