All the signs are there.
We were at the Mets/Marlins game August 10th, 2008 and climbed all the way to the top of Shea Stadium's Upper Deck Section 48, just across from the embryonic Citi Field.
The new scoreboard with its version of DiamondVision and with the Cifi Field logo are visible. You can also make out the NL and AL out-of-town scoreboard and the outfield seats.
One observation: from the top rows of Shea Stadium, the top rows of Citi Field don't seem much lower to the playing field. If there are 12,500 less seats, where did they all go?