Is Yahoo! too large a company to force into Microsoft's ways? That's the question asked this morning by The New York Times, whose correspondents John Markoff and Matt Richtel report a Silicon Valley executive as declaring that, when it comes to overall technology mindsets, Microsoft and Yahoo! “are completely at odds with one another.”

The executive in question was CEO of SideStep, and had been a Yahoo! executive in charge of shopping, auctions, travel and real estate before leaving the company in 2006.

Another quoted expert is Brady Forrest, who was was part of a small music start-up acquired by Microsoft in 2000. "Yahoo! is just too big to switch over,” Forrest declares.

The New York Times article raises the whole question of Yahoo!'s IT inrastructure (Yahoo! uses principally FreeBSD with Java and PHP). Rasmus Lerdorf, creator of PHP, is even an infrastructure architecture engineer on the Yahoo! payroll.

Markoff and Richtel write:

"Microsoft and Yahoo! have drastically opposite philosophies on open-source software. While Microsoft has used some open-source code, it has generally not contributed technology to the open-source community. In contrast, Yahoo has been an extensive contributor and has built its internal computing platform almost entirely from open source."