2 million drivers !

When Vista was released to manufacturing (RTM) in November, it had 1.4 million device drivers, three times what XP had at RTM.
At the January launch, there were 1.7 million drivers, and now that number is close to 2 million.

When a consumer installs any new operating system, the software generally polls the attached devices, and attempts to match them to its list of drivers. For Windows 2000, only 350 devices were installed in the box; for Windows XP, 10,000 drivers shipped with the operating system. With Vista, 20,000 drivers came bundled with the operating system. Windows Update, the stopgap method if a driver isn’t found, included 2,000 additional drivers at Windows XP’s launch, and 13,000 drivers at the launch of Vista.

Source: http://vista.blorge.com