So Act Network v. Twitter, No. _____ (Ill. Cir. Ct., Cook County  filed Nov. 16, 2009).
Status: Pending.

Social Action Network, operator of the social networking site SoAct!, filed a petition for pre-suit discovery naming Twitter, on order to obtain information to identify a tweeter who, using the pseudonym bobandscott, it alleges is sending defamatory messages about the company.  (The tweets also appear on the Bob and Scott website.)  According to the suit, the offending comments allege that So Act Network is involved in various financial frauds and stock manipulation.

Links and Court Documents:
SoAct wants Twitter to identify the users defaming it (Chicago Bar-Tender blog,  Nov. 19, 2009).
>> Petition for pre-suit discovery