Report Offensive Message
Go a bit deeper
The study doesn't say that 20% of businesses 'use it' as in have all Google Apps products fully deployed across the organization and being used by everyone - that is pointed out in a few different places. The stat refers to how many have deployed it in some form, so you should think of this as 20% have 'tried it'. The study also says that 1/3 of these deployed mail, and 1/3 deployed enterprise wide so multiplying those out, the companies that 'use it' in the way you are thinking is probably low single digit percentage. Still pretty good take up for a product that is only a few years old.