It is stated on the press to always stir the grounds prior to pressing down.
However, people I trust have stated otherwise.
Stirring the grounds could be a conspiracy by the coffee powers to somehow get consumers to buy more coffee. (assumption, stirring grounds reduces the amount of consumable coffee).

August 29th, 2009 at 4:08 am
That’s really interesting. I’ve never used a coffee press, but have always been curious about them. I like loose leaf tea which utilizes a similar method to your coffee french press.
I’m not sure how the coffee grounds react when hot water is poured in, but if they scatter and float around, I dont’ think stirring makes much difference since each coffee ground particle gets exposed to water. Stirring would probably “increase” the amount of consumable coffee since the motion of the particles would release more oils and flavors…just my opinion.
August 29th, 2009 at 7:13 am
I stir them -
I’m not sure I understand why stirring them would reduce the amount of consumable coffee.
August 29th, 2009 at 2:04 pm
I agree with Kays answer by stirring you’re releasing the flavor of the coffee when you press it down you’re still going to get the same amount of liquid.
August 29th, 2009 at 6:55 pm
We stir ours each morning, but with a non metal spoon.
August 29th, 2009 at 8:00 pm
I always stir mine, and when I pour it, I run it thru a paper filter. Unfiltered pressed coffee can cause a rise in cholesterol.
See http://www.msnbc.msn.com/id/6242467/