At Microsoft’s annual meeting with financial analysts Thursday, founder and chief software architect Bill Gates said he was pleased with the progress of Longhorn, the next major version of Windows, but also called it “a big bet” for the company. “We don’t know the exact time frame, but it’s many years of work,” Gates said. Jim Allchin, head of the Windows division, said the company plans to introduce a beta version of Longhorn “late next year,” according to Dow Jones Newswires.