NASA also has a presence in Second Life along with a number of other science-related organizations. We have formed something of a region called SciLands. Maybe one of the best ways to try SL out if you haven’t done so already would be to show up for one of the regularly scheduled meetings. We have NASA CoLab meetings on Tuesdays at 4:00 Eastern. Would be happy to share the landmark with you if you like. I know MuniGov 2.0 also has weekly meetings on Wednesdays at 7:00 Eastern I think. Are you familiar with the Federal Agencies in Virtual Worlds Consortium? That would be another way to find out more about what govt agencies are doing in SL.
To answer your question: I think the virtual world thing is where technology is going as it is about as interactive as you can get. It may not be Second Life in 5 years but I think it will be something else.
Let me know if you get in-world; just im Universa Vanalten.