You'll probably need to consider the ceiling height as well.

Do you require dimming?

How bright do you want the room to be?

Two fixtures will not look silly. I mean, I wouldn't do two chandeliers, but two pendants over a table of that length will look fine and very "up-to-date."

If I had a table / dining room that size, I would use two of these. I'm in love with the lantern style, and would definitely use these in my house; unfortunately, I do not have the appropriate place to put one.

Here is a link that might be useful: Regal French Chandalier (pendant)

A center chandelier with a recessed fixture on either side. Keep the recessed fixtures over the table and not over the heads of the people at the ends of the table. For minimal visibility use a 3" or 4" low voltage fixture with pin spot trim and lamp appropriate for the ceiling height. If cost is an issue use 5" recessed with Par 30 lamps.