A phenomenon on this side of the pond?

I went to Borders today to buy "Eats, Shoots & Leaves."

They were out.

The clerk said the store had sold out of their 14 copies fairly quickly. More will be in tomorrow or the next day.

I checked out the stats on Amazon when I got home and found a few interesting things.

First, the book is second on their Top Sellers list, second only to Bob Woodward's book. Ahead of three books on the South Beach Diet. Ahead of Richard Clarke's book. Ahead of "The Da Vinci Code" and an Oprah's Book Club selection. Wow.

Second, Borders was going to sell me the book for the list price of $17.50. Amazon.com has it for $12.25. Then I see this section that says "Available for in-store pickup now from $10.50." And, what do you know, I can get the same copy of the $17.50 book for $10.50 at the same store by going through Amazon.

I like saving $7, but I have a question for those of you who know such things: How does this affect the author's cut? Would she make a higher percentage from Borders than from Amazon? Does it matter? What if I bought a book an author's Web site?