But overall IT spending and employment growth will be modest over the next few years, according to this Microsoft-sponsored .

By the end of 2010, more than 177 million copies of will be "in place" worldwide, with about 60 million in the U.S. The Windows contribution to this growth will include $41 billion in the Microsoft ecosystem spent by the end of next year by companies that are developing, marketing, supporting and developing services around Windows 7, IDC reported.

Howeverm, won't dramatically reshape IT spending. Market research firm IDC also estimates that IT spending in the U.S. this year on hardware, software and services will reach $525.5 billion, and increase about 2% to $536 billion next year. Spending through 2013 will see a compound annual growth rate of 2.3%.

In terms of jobs, IDC is predicting about a 1.5% increase in next year, for a compound annual growth rate of 1.6%. IDC counts nearly 11 million people working in tech today, but this includes everyone from engineers, who design software, to retail clerks, who sell computers. "The fact that it is growing at all is pretty good," said John Gantz, one of the analysts who prepared the study of the employment growth.

The overall market for Windows continues to expand. Its software now runs 56% of all the software in the world, from 50% in 2007, said Gantz. He said much of the gain has been the result of a shift from RISC-based to Intel-based architectures, but "we do feel that Windows 7 is a net creator of jobs."