HTC says that if you own one of their 2012 devices with 512MB RAM, there is a better shot of a full Beatles reunion than of you getting Android 4.1. OK, they didn't say it exactly like that, but you catch the drift. There have been two models launched this year with 512MB of RAM, the HTC One V and the HTC Desire C.
HTC says its Android 4.1 update will come with HTC Sense 4+. Check out the sourcelink for HTC's answers to frequently asked questions about Android 4.1, like why it takes so long for updates to reach your phone. There are a number of buzz words and catch phrases in HTC's response. As you read their reply, think of a pinball machine with the ball bouncing off the bumpers, "Our goal is to make sure that an upgrade provides an improved customer experience (BING!) and that means a high standard of quality (BING!) for hardware compatibility, adapting device or carrier specific customizations, testing by HTC and partners (BING!), addressing device hardware constraints, and many other factors."
Hopefully, your HTC device will make the cut and sometime in the not too distant future, will be powered by Android 4.1. Lost in all this though, is that the most recent Android OS build is Android 4.2.
"We work hard to ensure each of our products has the optimal user experience and therefore some products will remain at their current version of Android. In general, devices with 512MB RAM or less will not be upgraded to Android 4.1. At present, these devices include the HTC One V and the HTC Desire C. As we identify other devices that will not be upgraded, we’ll provide updated information."-HTC
source: HTC via Phandroid