Not a big surprise here, but it\u2019s worth noting: The worldwide market for handheld devices began 2006 with its ninth consecutive quarter of year-over-year decline, with shipments of just 1.5 million units -- down 22.3 percent from the same quarter a year ago. All of that is according to IDC's Worldwide Handheld QView.But what about all those BlackBerry and Palm Treo sales? For this research, IDC defines handhelds as the pocket-sized, either pen or keypad-centric, devices that are capable of synchronizing with desktop or laptop computers, and are designed to access and manage data including office documents, multimedia and games. The important distinction here is that these \u201chandhelds\u201d do not include telephony functionality (which would technically make them a smart phone), though the handhelds may include some wireless capabilities that enable Internet access and text communication. The report states the obvious: \u201cDespite the incorporation of features like Bluetooth, Wi-Fi, expandable memory, and integrated GPS solutions, the handheld market continues to shrink. Many of these same features can be found on mobile phones, and the inclusion of telephony extends the usability of mobile phones beyond that of handheld devices.\u201d And, in response to changing business conditions, many of the vendors have started producing smart phones as well, the report notes.The top-five sellers were Palm, HP, Dell, Acer and Mio. If you look at Palm\u2019s data from the IDC report, you can see the trend toward smart phones playing out: While Palm remained the worldwide leader in the handheld market (even though its shipments were 23 percent less from the year previous), its shipments of its line of Treo smart phones continued to increase and actually surpassed its handhelds shipments. (For kicks, I just rummaged around for my first -- and last -- handheld device that I purchased, which was gathering dust in my \u201celectronics graveyard\u201d box. Ahhhhh ... the Palm 105!)How about you? Has your company made the switch? Are you still hanging onto to your handheld and using a cell phone as well? Let me know your thoughts.