According to their FAQ:
Languagelab is built on a virtual platform called Second Life that has substantial computer requirements. During the registration process you will be asked certain questions to determine if your system is compatible. Most newer computers with good graphics cards will meet these requirements.
Languagelab makes special use of the Second Life voice system that enables participants to speak and listen to one another in real time, both individually or as a group.
At the moment we are running our Beta test where we invite participants to use the service free of charge. In return, we ask for feedback on what needs to be improved. Currently we are offering classes in English with Spanish coming soon. More languages will be available in the near future.
So for those of us who do not have the funds to buy an island, this might be an interesting option. Comments?