FYI => First, be warned, the AddThis documentation isn’t accurate and up to date.

http://AddThis.com

In the process of fine tuning the Xero Xero Five machine (XeroXeroFive.com), I came across this:

=> When using the addthis_share parameter to configure your own URL shortener, the AddThis document specifies the use of username. The actual label in the setting is login:. That is, …{bitly: {login: ‘mylogin’, apiKey:R_myAPIkey’}}

=> If you’re wanting to use Add URL Parameters and want to have more than one AddThis button per page, you’re probably going to run into some trouble. Unfortunately, the documentation doesn’t mention this limitation.

That said, the turn around on answers in the AddThis forum is usually about a day. Not exactly blazing if it’s crunch time but better than a number of forums I’ve posted to. That is, no reply at all. The AddThis crew also seems to be very open to new ideas, feedback, etc. What they don’t seem to do is update their documentations.