Consider the market share of Microsoft Office, long estimated to be around 90 percent.  Since that’s not firm and not everyone has a computer, we won’t try any math at this point, but the world’s population is in the neighborhood of 6.7 billion people.

Google’s Docs and Spreadsheets sites, in contrast, saw about 3.5 million and 2.6 million American visitors last month, respectively.  A Compete article on Seeking Alpha also states, “Unique Visitors to Docs visited an average of 3.01 days in September, 2008, while UVs to Spreadsheets visited an average 3.11 days,” and, “To add some additional context we see that on average visitors to Google Docs & Spreadsheets spend about 5 minutes per month on the site.”

So we’re not exactly seeing a free software revolution.

Google Docs and Spreadsheets is becoming more popular, though, with 156 percent year-over-year growth taking place.  And with so many people both avoiding Vista and trying to save money, things may accelerate even more over the next year or so.