A story on Fortune today says that Apple’s share of the operating system market grew 3.34% in November to hit a record 6.81%, according to the results of a Net Applications survey. “Net Applications’ monthly surveys do not measure market share in terms of computer systems sold,” notes the report. “Rather, they sample data from visitors to some 40,000 websites operated by their clients. As such, their findings are probably better described as a snapshot of installed base taken from a less than random sample.”