Flickr: 704 API Calls per Second
www.programmableweb.com/2008/04/23/flickr-704-api-calls-per-second
From the page
Saved with the link. Notes from 2007 to 2016 are mostly the page's own words, so this is probably an excerpt.
As announced on the Flickr Blog, Flickr has launched a new website for developers: Flickr Code. And besides announcing the new site theyve both a) given interesting details on just how much API traffic they do each day (see below), and b) they announced theyre open sourcing Flickr Uploadr, the cross-platform (Windows and OS X) desktop tool for uploading photos to Flickr.