I will most likely be switching over to T-Mobile and went into the store by my house yesterday with some questions.
I am currently with AT&T and heard the news yesterday that T-Mobile would pay your early termination fee if you leave before your conctract is up (the catch being you have to trade in your phones for the trade in value that they offer you and purchase new phones from T-Mobile).
For the two current phones on my AT&T plan it was a measly $40 trade in value for My Lumia 920 and a $31 Trade in Value for the HTC 8x on my second line. So as I mentioned above after you trade them in you have to purchase new T-Mobile phones.The problem is that they only have two Windows Phones to choose from: The 925 and 521. This would be fine if I knew they were going to be getting the 1520 or a variant of it in the near future but the sales representative had absolutely no idea at all if they were ever going to get it.
I would love to switch to T-Mobile as the price of the phone bills would save us about 60 bucks a month plus I get a Corprate discount through my work with T-Mobile as well (no corporate discount with AT&T currently). I just wish I knew if they were going to get newer Windows phones anytime soon. I think what I will end up doing is switching to T-Mobile, going with the Lumia 925 for both phones, paying for the "Jump" plan on T-Mobile and switching phones once they get a new Windows phone.