I just go the HTC One from my 2 year old iPhone 4S :D, and I had some questions about updating Android and it's different versions. I'm running Android 4.1.2 (out of the box), and I was reading that 4.2.2 and 4.3 have already been released for the HTC One. Whenever I go into settings>about>software updates, it says my phone is up to date. Is this the current version, can I update to 4.2.2 or 4.3, or do I need to wait to update?
It more than likely sounds like fellow HTC One user are using custom roms to get the newer updates.
Installing custom roms always carries a risk of 'bricking' the device but the risks are very low, I've been doing it for years with at least a dozen phones and never had problems. There are specialist sites out there like XDA who have an entire world of modding in that way.
I did read that HTC One will be introducing 4.4 (kitkat) to the Google Play Editions and the 4.3 OTA (over-the-air) update is delayed but will be released so you can either wait it out or dive in to custom rom flashing.
I know with 4.3 and 4.4 coming out it may seem like 4.2.2 seems old but applications will fully support 4.2.2 for a long time so there is not absolute need to update other than really wanting to :)