PlayStation Vita firmware 3.67 is now available to download. Sony has released the second PlayStation Vita system update of the year today. It’s currently unknown what the update adds if anything (it may very well just a piracy prevention update), as Sony hasn’t updated the official website yet. We’ll add in the details when they’re released.
If you’re having issues updating your PlayStation Vita, here are the notes from Sony’s site:

Do not download or install the update using data other than the official update data provided online or on a PS Vita card by Sony Computer Entertainment. Do not download or install updates by methods other than those described in the system documentation or on this website. If you download or install update data from a different source, by a different method, or on a PS Vita system that has been altered or modified in any way, the PS Vita system might not operate properly and might not be able to install the official update data. Any of these actions can void the PS Vita system warranty and affect your ability to obtain warranty services and repair services from Sony Computer Entertainment. This update is for PS Vita systems purchased in North America. DO NOT update your PS Vita system using this website if you purchased your system outside of North America. There is no guarantee of proper operation with models sold outside North America. For details about PS Vita systems purchased outside of North America...