PalmOne has released two new models of their ever popular Zire series of handhelds. The Zire 31 is a color replacement of the Zire and Zire 21. It still features the two buttons on the front, but gains the five-way controller. The color screen is only 160x160 and is STN. The Zire 72 replaces the Zire 71. Lost is the cool slider design of the Zire 71. New is the 1.2 megapixel camera, the ability to capture both sound and video, and also Bluetooth connectivity. The Zire line has been Palm's more popular and better selling line of handhelds, it represents their low-end with the features from last year's high-end models. I can see why it sells so well because of this. These are nice replacement models, but how much longer will people be picking up stand-alone handhelds when smartphones (much like PalmOne's own Treo600) are picking up so much momentum? Infosync World has a review of the Zire 31 (6.8/10) and of the Zire 72 (7.2/10).