Actually no. This is directly from the Seattle Times article on the folding wingstips. They were originally offered on the 777-200, and were 21 feet long.
The 777-x proposed folding wingtip is only 10 feet long.
The folding wingtips on the 777X are far removed from those proposed for the original 777. Unlike the original folding wing tips, these are outboard of any flight controls or other moveable surfaces aside from the folding wingtips themselves.
The new wing on the 777X is wider span than current 777-300ER - the folding portion is intended to get the 777X into the same gate footprint as the -300ER. The designers believe they can get the associated weight penalty small enough that drag improvement from the greater span overwhelms the weight penalty. Further, the folding section is small enough that even if it should fail, the aircraft would still be airworthy.
No first hand knowledge, but I'm hearing that on the 777X, the folding wingtip will be basic, not an option.