Obviously SL isn't the only player in town but it is nevertheless significant that it is moving towards making it possible to import and export from other environments: modelling tools like 3D Max or other virtual worlds.
3pointD.com: Second Life Build Tools Support More Formats
Not that I need to spell it out, but if this is the start of a pattern then we will see greater incentives and lower risks to museums (and everyone else) to invest in Second Life, or more fundamentally in virtual objects that might be used in such environments, and corresponding improvements in sustainability.s
And why do I ALWAYS insert an unnecessary "e" in "environment"?