T-Mobile says v4.6.1.231 is the latest they support. Does that mean it's unsafe to upgrade?
Nope, not at all. Please read the BB101 Lecture Series as well as other upgrade procedure threads to get a firm base and knowledge of how to upgrade/downgrade your OS as well as how to troubleshoot in case something goes wrong. If you have any issues with your device CB will offer you a million times better support than T-Mo ever will so you have nothing to worry about.
Just put in the time to read, research, and learn everything there is to knopw about your device and BB's in general and get familiar and comfortable with your device before you start to tinker with it. The more time you put into reading and learning the better experience you are going to have.
T-Mobile says v4.6.1.231 is the latest they support. Does that mean it's unsafe to upgrade?
Not really. For example 4.6.1.250 is official by RIM but T-Mobile hasn't given
it a carrier specific "ok." Are you running .231 right now? And if you are what
issues are you running into that give you the desire to upgrade?
I've done so many OS upgrades since I got my 8900 in January that I have forgot how many I've actually done... my original OS was .114.
Recommend you read as much as possible before starting any OS upgrade... that also means you need to become very familiar with your device before performing an OS upgrade as well... there is a great starting thread in the Blackberry 101 lecture series (can be found under "Blackberry Help" at the top of EVERY Forum page)... also read the upgrade/downgrade procedures thread in my signature below.
