The image is from the proverbial "trusted source" who also told Android and Me that LTE will be coming to Virgin Mobile as well. No other details were provided so we don't know if this means LTE phones will be eligible for the rumored Boost Bring Your Own Sprint Device program of if there will be Boost and Virgin Mobile branded LTE devices.
However the scan is rather suspisious in that the phone shown, the Samsung Galaxy S II, is not an LTE capable device. But Boost's marketing materials sometimes contain gaffes like that. For example the Boost web site lists the 1xRTT (2G) Samsung Factor as a 3G phone.
Perhaps more telling is the small 237 x 300 px size of the image. Usually when these leaks show up one can findreasonably large, say 480 x 640 px, version of the image somewhere on the web. Perhaps the small size is meant to hide some otherwise obvious photoshopery. Due to small size of the image and the lack of details I'm putting this "leak" firmly into the un-confirmed. un-corroborated rumor categorey for now.