i got a 16gb microsd off of amazon for under $14.00 and it holds just little over 8k books, it was what swayed be over the kindle fire, that and the 1gb of ram vs 512mb. Now that they released a 8gb nook for $199.00 its price point is on par with the fire, and has the option of expansion, and  a simple hack allows for a custom android launcher, and i can easily install the amazon app store(and kindle app), android market place, and have a very decent wifi tablet, tbh i wasn't much of a analog book reader, but with this little nook tablet i've been averaging a book a week, along with .99-1.99 monthly magazine subscriptions.