I don't know for sure but most likely they're doing it for the same reasons they proxy images: Better protection against malware Source: http://gmailblog.blogsp

I don't know for sure but most likely they're doing it for the same reasons they proxy images: Better protection against malware Source: http://gmailblog.blogspot.com/2013/12/images-now-showing.html http://gmailblog.blogspot.com/2013/12/images-now-showing.htm... Additionally I would assume that they may use the data for analytics and advertising in order to display more relevant ads. Another possibility would be to complement the site data they got from crawling websites.