In message , at 09:01:19 on Sun, 14
Dec 2008, David of Broadway remarked:
the remaining balance can be transferred to a new card at any station
booth or MetroCard Vending Machine until two years after the expiration
date (recently extended from one). After that, I believe the balance
is lost permanently.

So my impression from 2004 was correct.

If you're an infrequent visitor to New York, I suppose that means that
you should try to use up your balance before you leave New York.

I'd be unlikely to visit NY more than once every two years. It's been
4.5 years at the moment, and no visit in the pipeline.
--
Roland Perry