Obviously he's not fine or else he wouldn't have had to have two MRIs and drive down to New York to visit the team physician. But according to Pat Hanlon's Twitter just a few minutes ago, those tests and exams showed no severe damage.
Here's the Giants' statement:
"Hakeem Nicks hyperextended his right knee at the end of yesterday afternoon’s practice. He had an MRI here in Albany last night. We sent him down to Hospital for Special Surgery this morning for another look, a precautionary MRI, and so Dr. Russell Warren could examine him. MRI results and Dr. Warren’s exam showed nothing out of the ordinary. In other words, Nicks’ knee is fine."
Now obviously he won't be trotting out onto the field tomorrow. Or maybe he will, who knows? The point is that he probably won't miss any regular season time and should be back soon.