Coming on the heels of its color BlackBerry 7210 and 7230 for, respectively, AT&T Wireless and T-Mobile services, Research in Motion (RIM) raises the bar further with the BlackBerry 7510. Largely resembling its predecessor in size and shape (with the exception of an included antenna), the new model adds a speakerphone, the first for a BlackBerry device, and a connection to Nextel's Nationwide Direct Connect Push To Talk service. Its initial price of $549 is a bit on the high side, but Nextel is offering a $200 discount for new customers signing a one-year contract.

Upside: The 7510 promises to pack a lot into one package. A phone, a Web browser (through Nextel Online's wireless Web), e-mail access, and an organizer are all included, and the addition of the speakerphone is a welcome plus over Nextel's previous 6510 model. Its other features are largely the same as those of the 7210 and the 7230: a 65,000-color, 240x160-pixel display; a QWERTY keyboard; and a thumb-operated trackwheel, as well as support for Java and real-time e-mail with attachments.

Downside: Though the 7510 has 16MB of flash memory and 2MB of SRAM, it lacks a memory expansion slot. Also, this model works on Nextel's 800MHz iDEN network in the United States only and not abroad.

Outlook: The 7510 looks like a good match for Nextel's business-oriented users who want--and can afford--to make the switch to a sophisticated smart phone. However, its ultimate success will depend on a sub-$350 price point.