A sry, but where did you find what, a zip to download? If you're still stock you will get fota update from your carrier, if not take a look at the development section, there are many sense 3 roms, also stock ones.
Yeah, it's an official build from HTC. But it's not rolled out for all people for now. So you have to wait to get an update notification (depending also on your carrier) or flash it manually. For that give a look into development section. There are prerooted stock roms and also tweaked 3.0 Roms
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