Apparently Eastman is under a manditory suspension as a result of injuries sustained in a K-1 fight in Vegas and is not eligible to fight on the UFC 50 card. Patrick Cote posted on a French forum that Ivan Salaverry was the replacement.
I personally like Salaverry more than Eastman. He has a broader range of skills and his fight with Semenov was awesome.

That should be a great fight. Two great srikers going at it can't be bad