"Gartner Group recommend that companies delay deployment of critical Linux applications, determine "whether Unix or Windows will provide functions equivalent to those of Linux deployments", and take a "go-slow" approach to Linux in high-value or mission-critical production systems."
(Quoted on Slashdot and in The Register.)
As it turns out, as far as their internet presence goes, big companies are doing the exact opposite; over 100 enterprise sites run by probably the very same Fortune 1000 and global near equivalent companies that recieved the SCO letter have switched to Linux since May, including Schwab.com.