[He's grinning right back, even though for him he's only just seen the Doctor -- old habits die hard, and this one harder than most. He's been away from the Doctor too long to not be pleased at seeing him, even here.]

I've got business at home, is all. And I'm pretty sure Gwen will kill me in either case, but -- [A shrug.] You're here. That means we'll get out soon enough anyway.