According to this BBC article, more art is sold online than in galleries. This is the first I’ve read of this. Over the past few years there has been an ongoing debate, and even a snobbery perhaps against online galleries. It seems the tides have turned!
Read this article, including a quote regarding Saatchi online gallery sales vs physical gallery sales—http://www.bbc.co.uk/news/technology-23054641
PLEASE NOTE: Keep trying the links–you may receive an error message, but you will get through to the article if you keep trying.