First, this deal is only good for the photo books you create in the store. You cannot make your photo book online. You can, however, plan your book at home so that your time spent in the store at the kiosk is minimal.
Decide what you want your book to be about. The deal is for a 10 page photo book. The first page can only have 1 photo but the other 9 can have up to 4 pictures. So you'll need anywhere from 10-37 pictures for your book. The pictures print only on one side of the page and print on glossy paper. You can burn them onto a CD, bring in the card from your camera, or bring in a USB drive. I brought in a USB drive with the pictures on it that I wanted for the book. Make sure to clear your USB drive (or a CD) so only the pictures you want in the book are on it.
Go through the pictures you choose and edit them on your own computer. Crop, fix red eye, rotate, etc. Then figure out which pictures you want on which pages. I just did a piece of computer paper and rough sketched my pages on there. I then renamed the photos to correspond to the page number (i.e. for a photo on the third page, I named with a 3 in front of it). I also put on the piece of computer paper a short description of each picture for each page. This turned out to be a lifesaver in the store.
Luckily there wasn't a line at my store but I was reading online that the stores ran out the last time the promotion ran. I put my USB into the appropriate drive and the process was rather intuitive. Make sure to choose "photo books" then 6x8 to take advantage of the special this week. The machine ends up putting your pictures wherever it wants on the pages. My rough sketch helped and I was able in a few minutes to rearrange the pictures to be on the correct pages how I wanted them.
You are able to choose a background (I chose several of the solid colors) and add text (and change fonts and colors of text) to the pages as well as increase/decrease the size of the pictures on the page. When you are done, it takes you through a confirmation process and my pages printed within a couple minutes. The lab tech will then put your photo book together.
The finished photo book is quite nice and would make a great gift for someone! The ad says limit of 1 per ExtraCare card but there are rumors online that the limit may actually be higher in which case I could roll my ECB's and make some more photo books. I'll keep you all posted if I find out that's true.