Apple isn't a huge fan of DRM because they saw iTunes MP3 sales take off after DRM was removed. They realise consumers hate it. Problem is of course publishers who would have no doubt demanded some kind of DRM with ibookstore ebooks. Apple also like to do things their own way which means they might not follow what Adobe has done with DRM.
So we could have epub with some new kind of DRM on top, but it's all conjecture. If it does have DRM, we shouldn't be too concerned a hack will appear to remove it pretty quickly. What I am interested in is if the Amazon app will be on the device. If it is, we'll have the iPad able to read epub and all of our Kindle books while the Kindle is off it's own little world with their proprietary format.
iTunes still has DRM on movies and TV shows. Steve Jobs thoughts on DRM:
http://en.wikipedia.org/wiki/FairPla...ic_open_letter