In case my other articles or reviews haven't made it clear, I'm a huge fan of digital comics. And for me the only choice worth looking at is comics via Comixology. Today when I turned on my iPad i was greeted by app updates for the main Comixology app, as well as the DC and Marvel apps. I would assume that the Image one will be updated soon as well. The publisher apps aren't always perfectly in sync but it seems like they are never to far behind on that stuff. For me, they have a feature I have wanted for years... Marking issues read/unread. I often reread books, and love that I now will be able to mark books as unread, making it easer to keep track of where I am. I can tell that the Smart Lists features are going to have their advantages, but the new user interface will take some getting used to. I'm really excited to try out more of these features (like the archive feature).
On top of all that, Dark Horse comics are now on Comixology. This is great news as they were one of the last major publishers (that I know of anyway) to not offer their titles on Comixology.
Here are the full release notes taken from iTunes.