You can get used to tinnitus if it's permanent, but obviously that's not a good idea. I have permanent tinnitus in my left ear due to an infection I had 8-9 years ago. I don't really notice it anymore, but I still can't hear things like speech very well if they're going into my left ear. The consonants get eaten up by the ringing. I used to have additional hearing loss in the ear as well, but that backed off quite a bit, and now it's just a little bit.
Man, when science cones up with a cure for tinnitus, and they restore my hearing to normal, the silence would probably seem really strange. :P
Fender Jazz Bass #1029