He may have a new body, but there's no question of recognition. He could hardly be mistaken for some other Time Lord, not now.
By the time the Doctor finds the Master--who, the Doctor has felt from the moment he regained consciousness, had got clear of the link that pulled the rest of their people back to their own little corner of non-existence--his old enemy has already solved the problem of his leaking life-force, and there's the Doctor's first method of approach shot. From the calm the Doctor senses, a calm he's never felt in the Master's presence before, he knows the drums are gone for good, so there goes his second. The Master is once more clean and fresh and expensively clad, so he doesn't need the Doctor for any of those things, either; that was always unlikely, of course, but the Doctor'd had some little hope. For perhaps the first time in his life, however, the Doctor has a Plan D. And from the little smile on the Master's now scrubbed and shaven face, suspiciously like his expression after the Doctor asked him to kindly stand aside, the Doctor thinks it might actually work. It had better. It was only that smile, the first time around, that convinced the Doctor that this experiment was worth trying.
"I'm still me, you know," are the first words the Master speaks, as they stand side by side on the windy plateau where the Master once threatened to crack open the Earth. "No inclination when passing a puppy in a burning building to do anything but walk on by. Or possibly slosh on some petrol."
"I know." The Doctor smiles, a smile that he's still getting used to.
"Still wouldn't say no to ruling the universe."
"Still think you're a self-righteous pain in the..."
There is a pause.
"I still forgive you."
"I still don't want your forgiveness."
"I don't think I like this face," the Master says, turning to consider.
"You never do, until they're gone."
"Well," the Master steps fractionally closer, "if I don't like your face, and I'm not plotting something requiring your admiration, and I don't want to join your fool's crusade, then what am I doing here in the first place?"
The Doctor closes the rest of the gap. This newest regeneration has left them seeing almost eye to eye. "I have it on the very best authority," he deadpans, "that your heart--one of them, at least--is cold and hard and petrified. And for that..."
It takes the Master a moment to catch the reference, and then he throws his head back and laughs. "Let me guess," he says, and stops. He brings up one hand, tousles the Doctor's mane of dark hair, gives it an abrupt upward tug so that it makes a vain attempt to stand on end, and tilts his head to one side, considering the effect. Then he slides those fingers down to the Doctor's bare neck, and leaves them there. "For that, I suppose," the Master's eyes spark, "I need a..."
He never does finish his sentence.
Neither of them minds.