NEW ORLEANS - If Microsoft was chastened by last year's antitrust ruling, Chairman Bill Gates gave no evidence of it last week as he laid out his mobile and wireless computing ambitions.

Speaking at the first Microsoft Mobility Developers Conference in New Orleans - purposely held near the annual CTIA Wireless 2003 conference - Gates presided over the launch of the .Net Compact Framework. This is a set of development tools, code and software objects that let developers quickly build applications for an array of handheld devices that use Windows operating systems.

Gates painted a rosy view of mobile computing trends. Then he issued what could be viewed as a promise, threat or statement of fact - or all three - with regard to handheld rivals PalmSource, Symbian and Sun.

"We are going to invest and invest and invest to get the most popular software platform because we believe in these [kinds of mobile and wireless] scenarios," Gates said.

He called the Microsoft Tablet PC operating system, introduced late last year, an "explosive form factor." He pointed to new software platforms for "smart devices," including sophisticated cell phones and even a wrist-watch-sized network device, dubbed Spot, versions of which watchmakers Citizen, Fossil and Suunto are developing. "We're taking familiar things [from the Windows development world] and bringing them to this new form factor,"he said.