I couldnt agree with you more IMB. Now, that would be a question of " if they were DEFINETLY going to make a GF4" than yes, put it in cgi. Theres nothing left for Micheal to do after part 3 than, well die. After the end of part 3 he retreats to Sicily and lives out the remainder of his life in misery. So, I suppose you mean a younger Micheal, but then again, his voice changed so much since Part 2. But I'd say in general if the film must be made, and follow the earlier exploits of the Corleone family, it could work. I know what you mean when you say Pacinos getting old, It really hit me when I saw Righteous Kill, he's 69 years old. But then, say if it were about vincent mike could have a very small role, or merely a cameo. that would be the way to do it, good thinking IMB.