comiXology released a native app front-end to their comic book pull-list service and fan site (www.comixology.com). Pretty sweet app with all the listings of the shipping comic books and a ton of previews.
http://itunes.apple.com/WebObjects/MZStore.woa/wa/viewSoftware?id=297414943&mt=8
http://itunes.apple.com/WebObjects/MZStore.woa/wa/viewSoftware?id=297414943&mt=8