Also, posting it to HN without the question mark in your title was totally bogus.
The API call that Michael refers to is related to the "Stats Monitor" feature of Shareaholic for Firefox that can be turned off at any time.
The Stats Monitor shows users the Compete.com stats for the page they are on. The API call is intrinsic to the functioning of this feature. For example, only by knowing which web page the user is viewing can the browser tool show the user information about that web page or Web site.
To disable the Stats Monitor, go to "Shareaholic Options" -> Display Options -> Uncheck Stats Monitor.
And, all users are now made aware of this feature upfront:
http://www.shareaholic.com/tools/firefox/welcome http://www.shareaholic.com/tools/firefox/upgrade
The Stats Monitor is only available in Shareaholic for Firefox.
If not, what is spyware?