I didn't hear of Neo Geo until around 1994, when I read something about the AES in a game magazine. Of course, arcade cabinets have always been nearly non existant here. I knew about Fatal Fury and Samurai Shodown, but only from ports.
I think a lot of people who are into games, might know some classic Neo titles, like the above mentioned, possibly King of Fighters, and most likely Metal Slug. I'm certain emulation can be thanked partly from this. But otherwise, I surprisingly often run into people (whom I didn't really consider console/arcade nerds) who notice that I'm into Neo Geo, and exclaim that Neo Geo is a really awesome system.
My biggest surprise was at a Danish convention related to Japanese culture last year, where I was asked to set up a gaming room. I brought my MVS, and a friend brought his AES. They were both extremely popular, and a lot of people seemed to recognise the system. Needless to say, I was very positively surprised! It was the only system that got to run constantly, where the other TVs usually played host for various different systems.