Wouldn't we all like to work for a company who will pay us $80,000 to take a year off of work? Granted, the $80,000 is only a third of the workers base pay--but I think many of us wouldn't have a problem living off of it (I wouldn't).
I think this is a brilliant plan to cut costs--especially since you are not required to take it. If you can afford to take the cut in pay, by all means--what an opportunity! In this case, the firm is a law firm, and many of the lawyers who are taking advantage of this program will be going out into the community and doing pro bono work.
You don't often hear good things about lawyers--more often the down and dirty stuff--so it is a relief to hear about a firm doing something to help their employees and help the community at the same time, even if it is all in an effort to cut costs.
Maybe I should go to law school...