Internet ran businesses that operate only online can be broken down into 2 segments. Thinking stage, and execution stage. I operate under the idea that if you can think of it, it can already be successful.
Research and planning happens within the thinking stage, but its called the thinking stage because the Internet changes as often as a 1 year old needs a diaper change. So there is a constant need for research and the developed plans will always need revising.
These business aren't 1 2 BAM, though. It's an organic process of jumping between the 2 segments thinking and executing. There are no set rules to running a successful Internet Only Business which is why I say a personality is the most important aspect of having a successful Internet presence, because personalities can change.