Sherman Hemsley's movin' on up days are officially behind him. The former Jeffersons star has been tapped to voice the title character in Fox's in-the-works remake of the talking-horse sitcom Mr. Ed. In other TV casting news, Taye Diggs has signed on to headline UPN's Mel Gibson-produced drama pilot Kevin Hill, which centers around a young attorney who gives up his playboy lifestyle to raise his niece. Finally, ABC has picked up an untitled comedy pilot starring Jennifer Love Hewitt as an on-air sports reporter.