In an interesting turn of events, it appears that Sprint might be releasing a new Windows Phone in the future. It is set to support 3G in the ESMR band as well as 1900MHz. Funny it doesn't appear to support LTE at 1900, but nonetheless, it is still a nice looking addition to Sprint's lineup. Picture files were released at the FCC database for the device on April 1, and it looks like a nice phone.
Source: http://www.phonearena.com/news/Is-the-LG-Windows-Phone-LS831-heading-to-Sprint_id28698
I'd like to see how many more non 4G smartphones Sprint plans on releasing.