I upgraded. Still the same old sh1t. Battery pulls to get messages, losing the radio for no reason whatsoever. Good luck with yours if you decide to take the plunge.
I would say that there are no major changes with the update, but my Berry seems to be running a little smoother. With 4.6 I had some lag issues and was getting the loading clock a lot. The upgrade has helped these issues, also receiving text is a little more consistent. If your not having any issues with 4.6 then I would say there is no major benefit to upgrading but you can always give it a try and if you don't like it just roll back.
Posted from my CrackBerry at wapforums.crackberry.com