As promised, ComiXology began sending out emails with personalized links to individuals who asked to be notified about the continuation of the Marvel #1 promotion. The email contains a link that can only be accessed from the email address it was sent to. The recipient has 48 hours to claim their free comics (over 700 in all) before the link becomes inactive. I just got my invitation, and can tell you the process worked flawlessly.
All of the eligible comics are displayed on a single page. The are separated by specific categories. The categories include Marvel Now! Avengers, Marvel Events, Marvel Zombies, Punisher, Ultimate Universe and a lot more. Some of these categories span across several pages, but you won’t actually leave the main page. The comics within that category are the only things that will change when you click on the next page.
Once you’re done, the checkout process only requires you to click a submit button. ComiXology asks for you to wait around 12 hours for all the comics to appear on your account. For me, the process took a few seconds. From there you’ll be free to download and read every single one of your free comics on whatever device supports ComiXology.