It's great news.
If you think about it, I think T-Mac still has a lot left in the tank. He's had some injury issues, but who knows? He COULD return to his former self, but I highly doubt that.
However, even if he returns to half of his former self, he's still far and away better than any player we have. He's an excellent scorer and worst comes to worst he'd be a great complement to a superstar.
I view his role for the Knicks the same way I view Grant Hill's role for the Suns, except I think McGrady is going to be way better than Grant Hill