It started in his eyebrows (such as they were), slowly rising, the perplexed, piercing (perhaps even disbelieving) squint of his eyes softening into surprise, and then clearly pleasant surprise as he smiled, somehow more boyishly than ever and yet at the same time with the wistfulness of seeing someone after being separated for a lifetime.

Which actually was sort of an understatement, from his point of view, but he didn't need to go bringing that up.

He glanced aside for a beat, then back to her, and raised a hand to wave with his fingers, himself, sort of sheepishly, still with that air of a cross between an elderly bachelor and a delinquent nine year old.

"...hello."

He relaxed more than a little when she did react, at least, and grinned at her quip, pointing at her like aha, well played.

"Ha, well, has been, yeah, still is, a bit, Rose Tyler..."

He clearly shifted trains of thought completely when he said her name--but then trailed off immediately like he wasn't quite sure what else to actually say. It was complicated for him, probably was for her also, and none of it was easily expressed in words without making it seem trite and absurd with banality. It wasn't the sort of situation where one simply asks how've you been? He even raised his hands as though to gesture something, but just ended up gesturing at her, like yup that sure is you.

Not that he could stop talking for more than a few seconds, his expression growing a bit more sheepish as a pertinent question came to mind.

"Sorry, ah, not quite sure but... how long..?"