Nick, the creator of a new great forum/blog named ThreadWatch posted an entry named WebmasterWorld Register Threadwatch.net - Is this a Wind Up?. Basically, it looks like someone over at WebmasterWorld, affiliated with searchengineworld.com, Brett Tabke, owner of WebmasterWorld - purchased the .net extension of the ThreadWatch.org domain name.
There is speculation that Brett commented at the entry. Nothing like good old forum cat fights. :)
{update} Brett informed me that he did this to secure the domain for threadwatch. He also purchased the seroundtable varations and offered to transfer it to me at cost.