Anyways, Here are the emoticons you'll get when you reach that level:
Karma Freeze is very simple. Just go to My Account on the top right portion of your screen and scroll down you'll see the Karma Freeze button, this is very useful when you are going on a longer vacation or don't have the time to plurk. However you'll lose around 0.5 karma as payment for the karma vacation. I don't know how long the freeze lasts but assumingly it can last very long.