They’re close, but not the same thing. BMR is measured in a dark room, lying down, and having been at rest for a certain amount of time. It is the lowest energy expenditure you’re body is capable of at certain point. 1 MET is close, but it is quietly sitting in a chair. You can have below 1 MET.
(I thought I knew this from memory and it was confirmed on wikipedia http://en.wikipedia.org/wiki/Metabolic_equivalent