But it isn't just the environment itself that has been recreated -- on the anniversary of the shooting, there will be a re-enactment of the assassination. This sounds a bit like one of those interactive history-museum displays. Due to the population limits within the simulation, this event will be invite-only for around 40 people.
If anything, it's a novel idea and worth checking out if you already play SL. You can get there by searching for Dealey Plaza Dallas within SL, or from a link on Avatar Promotions' JFK page.