So I signed up for this marvel.com/comics/unlimited/home?&options%5Boffset%5D=0&totalcount=12 (10 a month or 70 for a year). It's basically the majority of what Marvel has digitized so far for their back catalog, and six months behind on current books. The iPad app isn't as solid as the comiXology app, and the web version is also not as great as comiXology's web app, but pretty great, especially for the price of two books a month essentially.
That sounds like a super good idea. I just read Iron Fist #1 and it is was pretty amazing. Marvel is doing a really good job right now, it is really surprising. I'm not reading their main books though.