We have not done anything with Isposure in tbbmeter for sometime now, in 2011 we added an automated testing module to tbbmeter where we had control of the tests. Once that testing was over we disabled any further testing.
The tests used are included in the tbbmeter test tools if you want to run them.
Version 2 should give people the option for setting up their own testing schedule. But don't hold your breath, have plenty of other things on the wish list to do first