We should expect a period of time whereby new OpenSims pop up and disappear. As it becomes possible to "roll your own," everyone and their dog will think "hey, I can do better than Linden Lab" and promptly set up a virtual space. But as the number of "alternatives" increases, the number of residents may not. If Second Life can only get around 70,000 folks online concurrently, how would 100 OpenSims do this?

Of course, the natural way of things in business is for a plethora of "hopeful monsters" to be spawned and some may well offer a challenge to the beast at the top of the food chain. Meanwhile there will be new options for consumers and fun times ahead.