Apparently, Florio at ProFootballtalk.com thinks the reason for this admission by the Giants is to send a "message" to the Patriots about the validity of the injury report.
http://www.profootballtalk.com/rumormill.htm
GIANTS MAKING A POINT ON INJURY REPORT?
The second injury report is out for Super Bowl XLII, and it could be that the Giants are making their feelings known regarding the decision of the Pats not to disclose on Wednesday an ankle injury to Tom Brady -- but to reveal a right shoulder injury that apparently was suffered as he traveled down the birth canal, and that has never healed.
Typically, injured players are listed for only one ailment. On Wednesday, the Giants disclosed that receiver Plaxico Burress didn't practice due to an ankle problem that has bothered him all year. On Thursday, Burress didn't practice again. This time around, it was due to the ankle problem and a knee injury.
The possible message to the Pats and to the league? It's not good enough to name the player on the report without listing his actual injury. Indeed, it's possible that the Patriots have been using Brady's supposed right shoulder injury over the past few years as a way to avoid having to disclose any other injury that he might actually have.
For practical purposes, the league won't do anything to the Pats unless Brady doesn't play. But whether a guy plays is a different question than whether he's injured. And the idea that Brady's chronic shoulder injury is sufficiently severe to merit mention on the injury report while an ankle that required him 10 days ago to hobble around Manhattan in a walking boot is omitted provides ample justification for the Giants to believe that the Patriots are playing games.
Elsewhere for the Giants, cornerback Kevin Dockey (hip flexor) and guard Rich Seubert (knee) fully participated in practice. Both were limited in practice on Wednesday.
For the Patriots, receiver Jabar Gaffney was limited due to a shoulder injury on Thursday, as he was on Wednesday. Brady again fully participated despite that gimpy right shoulder. For the second straight day, the ankle wasn't mentioned.