Your2ndPlace

As usual, this is a case of a perfectly reasonably action that's been badly communicated to the community. First of all, as you point out, there is no need for anyone to start slapping "TM" after every instance of "Second Life". If you're talking in a nominative way - ie referring to the product - and not suggesting any association between yourself and Linden Lab then you'll almost certainly fall under fair use of trademarks.