It will be interesting to see what happens. Lots of people know about the Kindle because even if they're shopping for other things on Amazon, they'll see Kindle ads. People go the B&N brick and mortar stores or website specifically to buy books, so it may be a smaller groups of eyes learning about the Nook.
How will B&N get the word out and will it be enough to make people aware enough to take a big enough chunk of holiday sales? Over time I think the nook will have more of an effect.
Edit: For some reason I read this to be about the readers not the ebooks. Sorry.