Perry E. Metzger [18/05/08 18:10 -0400]:
The Narita Express was pretty fast when I last took it. Not a Shinkansen by any means, but still pretty good, and it stops right inside the airport. (Also very comfortable, and it has assigned seating, although that's a bit of a problem for those who can't read the (two) kanji needed to find your seat...)
NEX has bilingual seat numbers, announcements etc .. everything (at least as of late march when I was last in Tokyo)