it really doesnt make any sense on either side. metro was in very good standing where they were at. they did not need this at all. 5th biggest carrier, #1 prepaid. and they were only getting better with the S3 coming and their potential upgrade to voLTE. it makes no sense for metroPCS to sign their life away.
eating metro isnt gonna save tmobile from going under. at best it will delay it a year or two.
how can you hold someone to a promise they never made to you? - common sense