After the expected release of the HTC One Max, all HTC One models, the HTC Butterfly S and the HTC One mini will have Sense 5.5 together with the Android 4.3 update. Some HTC models will not be getting Android 4.3 such as the HTC One S and Sprint's HTC EVO 4G LTE. If you own those two latter models, sorry. That's just the way it is.
source: @LlabTooFeR via AndroidCentral