Help get this topic noticed by sharing it on Twitter, Facebook, or email.
Yes, you can.
The iPod/iPad/iPhone uses the ePub format in the iBooks app. Just log into your oreilly.com account and download the ePub format to your device. The Safari browser will say it doesn't know how to read that file, would you like to open it in iBooks. Just tap on that and it will be copied to your iBooks library on the device.
For the Kindle, you want to use the mobi format and you can download it directly to your Kindle (if you can browse the web on it) or you can download the mobi file to your computer and then plug your Kindle in with the USB cable and the Kindle will mount like a removable drive. Then just copy the mobi format to the Documents folder on the Kindle.
I hope that helps,
O'Reilly Book Support