Sweetheart or stalker?

Question…is it flattering or scary if a potential researches you before the first date? Let’s say you meet a guy, have a bit of conversation, then exchange numbers. You chat with the fellow a few times and make plans for a date. By the time you go on the date you realize the person has done some extensive research on you. He’s googled you, checked out all your info on FB or myspace, or whatever form of social media you use. So on the date he begins asking you questions about things you know you didn’t tell him about. When you ask him how he knows all this stuff he tells you he looked you up to 1)get to know you better and 2) have more topics for conversation. Would you consider this flattering or a bit stalkerish?