The obvious answer is YES you should upgrade, but before you do you should first make sure you have updated all available apps through the app store. Once this is done, restart your device (iphone/ipad) and then proceed to the SETTINGS Icon and the on GENERAL and finally SOFTWARE UPDATE. It requires 3.2 GB of available room on your device so if you have filled it up it won't allow you to proceed until you have removed enough items. It will list them in size so I suggest removing the items largest to smallest leaving important ones like your Chrome browser (assuming you have installed the Chrome browser) and your Gmail app if you are using Gmail. I ended up removing about 5 or 6 items--mostly game apps that I haven't played for probably a year. Don't worry, once the update is complete you can always go back to the app store and re-install, even if you purchased it, it will remember you already own it!
Some people are holding off in case there are problems.. it is always best to perform a backup of your device so if you haven't done that for some time then plug it in to your computer and open Itunes and perform a backup. My belief is there are always going to be problems with certain apps initially but that goes without saying.. but with any new operating system, things are going to generally be much faster and if nothing else, it is a great way to clean house on all those apps you weren't using anyway!
