It will be successful because it's Steve Jobs amirite
More seriously:
It might. It might not. It really depends more on the music they record and put out more than anything. Or if they have the money to get it on the radio, if you want to be a tad cynical, and being it's Steve Jobs and Jay-Z I don't think the money will be any sort of issue. As for financially successful, if they go the online distribution route, it would cut a lot of costs of printing and mass producing, shipping, all sorts of little costs. Cut out not only the middleman but the entire front and just switch it to a different place.
That being said, mp3s are pretty LAME (oh look at me I made an encoding joke rofl) and I really love to own a physical copy of an album, but in this day and age of ipods, where you can take a massive amount of music with you, amongst many people the idea of owning an actual copy of an album just doesn't have the appeal.