Microsoft chief executive Steve Ballmer will launch a new version of the Pocket PC operating system at a San Francisco event on Thursday, joined by handheld makers and, yes, developers, developers, developers. A simultaneous Pocket PC launch party will be take place in London on Thursday. The major device makers that supported Pocket PC the first time around -- Compaq Computer, Hewlett-Packard and Casio -- will be there. Also on hand will be a number of new supporters, including Toshiba, NEC and Mitsubishi Electric. Microsoft first unveiled Pocket PC 2002, which was code-named Merlin, at a 6 September conference. At Thursday's launch, the software giant will trot out new devices that run the OS, as well as software and other companion products for Pocket PC-based devices. Backing from new software developers is also critical for Microsoft, which is looking to play catch-up with Palm in that area. Among the formerly Palm-only crowd supporting Microsoft this time around is Vindigo, which makes a popular electronic city guide. Supporting developers is one area for which Ballmer is now famous, thanks to the widely circulated video of him revving up a crowd of developers. The launch of the new OS comes two days after market researcher IDC asserted that Pocket PC has failed to steal as much market share from Palm as once predicted. Pocket PC-based devices continue to fare well in the minds of business leaders, according to a new IDC survey of corporate executives. However, IDC's newly revised outlook for the handheld market states that corporations just aren't spending as much on the handhelds this year as had been forecast. A decline in both corporate purchasing and consumer spending has led IDC to also slash its forecast for the overall handheld market. IDC says worldwide unit growth, originally projected at 50 percent over last year, will now range from 10 percent to 20 percent. Among the new devices expected to be shown off Thursday are two iPaqs from Compaq and two Jornadas from HP, as well as a US version of the Genio from Toshiba. The US version of Genio handheld will include two expansion slots for flash memory cards: one for Type II CompactFlash and another for Secure Digital. NEC is also expected to publicly announce its plans for a handheld using Pocket PC 2002. The devices are expected to meet new hardware specifications from Microsoft, including support for ARM-based processors running at 133MHz and faster. Most of the manufacturers are expected to say that they are using Intel's StrongARM SA-1110 processor. Compaq is also expected to announce wirelessly enabled products using Intel's Personal Internet Client Architecture, which is essentially a blueprint for building wireless communications devices. A Samsung executive told Reuters on Wednesday that the company will launch a Pocket PC-based device next year, but the company isn't making any announcement at Thursday's event. See the Mobile Technology News Section for full coverage. Have your say instantly, and see what others have said. Click on the TalkBack button and go to the Telecoms forum. Let the editors know what you think in the Mailroom. And read other letters.