h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

You can tell that you're in a really classy cinema when you get seating of either of these types:

1) Diagonal seating. Instead of each seat being directly behind the one in front, each seat is positioned behind the gap between the seats in front. So instead of looking directly over somebody's head, you are looking over their shoulders (which are, of course, much lower).
This type of seating is increasingly rare these days, and is usually only found in really old cinemas (or cinemas that don't have much of a 'slope').

2) Curved-row seating. Instead of each row of seats being straight, the rows curve around the screen like an arch. So no matter where you sit, if you face directly forward you will be looking at the middle of the picture. This seems to be a relatively new concept, and it's absolutely brilliant.

Another relatively new concept (well, in UK Cinemas at least), are double seats with a moveable middle armrest. That way you can push the middle armrest out of the way and get closer to your love interest if you have one.

Of course this isn't particularly useful if you don't have a love interest.