According to AppleInsider [1], TigerDirect, a company based in Miami, Florida, is suing Apple over the "Tiger" trademark use.

Actually, the company owns "Tiger", "TigerDirect" and "TigerSoftware" since 1987 and believes that the use of this name by Apple's for its new operating system "is causing confusion, mistake and deception among the general purchasing public."

The company, which sells computer hardware and software, has requested an injunction that may prevent tomorrow's Mac OS X Tiger launch.

UPDATE: A MacNN report [2] provides similar information, while AppleInsider has updated its article with additional information. It looks like the news first broke on Bloomberg [3].

UPDATE 2: MacWorld [4] provides more information on TigerDirect lawsuit.

UPDATE 3: MacMerc provides links to official documents related to the suit.