From the report:
Among those who plan to purchase an e-reader in the next 90 days, 40 percent said they will buy the Apple iPad. That’s well ahead of the 28 percent who will opt for an Amazon Kindle, 6 percent for the Barnes & Noble Nook and 1 percent for a Sony Reader.
There’s no surprise here; Amazon started promoting the Kindle as their “#1 Bestselling product on Amazon” the week before the iPad was announced, and have sent out noticeably more email campaigns promoting Kindle ever since. They’re visibly worried, and rightly so.