yes, the MAP sensor is "Manifold Absolute Pressure", measured in inches of mercury and reported via OBD. When the engine is not running, your MAP sensor becomes as barometer. So to find boost from MAP, convert inches of mercury to psi, then subtract 14. 7. 61 inches of MAP is about 15 lbs of boost.
but reading through the thread again, I note that the article said that the turbocharger "delivered" 61 inches of "boost". So that must be 61 inches above normal atmospheric pressure (thats what boost is) or about 30 psi of "boost". What was initially confusing is that boost is almost never given in units of "inches of mercury" whereas Manifold Absolute Pressure is always reported (by OBD) in those units.
So I think the article just did what statisticians do best: express a mathematical quantity in the unit that delivers the most impressive message with a big number. They probably just took the nominal wastegate setting in psi and converted it to inches of mercury for effect. If they wanted to be really impressive, they could have said that the turbocharger delivers an intake air pressure equal to 91 inches of mercury.
I set my OBD MAP gauge to read 0 to 100 inches of mercury, knowing that 90 inches is approximately 30 psi boost. I acheive 61 inches routinely in daily driving.