http://newsroom.t-mobile.com/phoenix.zhtml?c=251624&p=irol-newsArticle&ID=1915221&highlight
Looks like the Lumia 521 & 925 are getting the software update to Windows 8.1 (see T-Mobile press release link). So if T-Mobile can send an update on Lumia phones, how about an update for the HTC 8X? Will we get Windows Phone 8.1 as an OS update (assume GDR3 will be rolled into it), or are we out of luck (seems like Lumia 810 owners are too). Please some information would be great. HTC has already announced that they are working on getting Win Phone 8.1 on the 8X. Question is will T-Mobile roll it out to the customer base or are we being burned again.