@winterstar True story. I've actually had both Griselbrand and Emrakul get Metamorphed in tournament play believe it or not. I was able to win the Emrakul game by Stripmineing a land to put my opponent to exactly six permanents and then enjoying the first attack phase with a non-summoning sick Emrakul.
The Griselgame I lost terribly, since the opponent just drew a crap-ton of cards and put so many lock pieces on the table that I was done playing things ever. It was a boarded game, so a pair of cages came down as well and I was stuck. The Grisels traded and that was that. I think I scooped to Factory beats.
Never had a Titan get Morphed... that does make me think of one more good thing about Titan though... You could just turn your Orchard sideways again and Oath into a second copy of Titan... pretty unlikely the opponent is sitting on a second Metamorph... good winning chances. And if you ever get to swing with both Titans at once you melt their Titan entirely.