Review of All Japanese All the Time www.alljapaneseallthetime.com
All Japanese All the Time claims that through doing the things you enjoy, you can become fluent in Japanese without ever taking a Japanese language class. The site is inspiring, and certainly worth a look, but there are some points to keep in mind before embarking on the approach outlined on the site.
First, the input before output principle is solid. This is definitely something you can and should apply to your studies.
On the other hand, the idea that you can read only what you enjoy and become fluent in Japanese-- well, it depends on what you mean by fluency. If you want to navigate a business situation well, you're going to need to know not just about business, but about politeness levels in speech. Since these vary in Japanese depending on your social position, they're hard to simply absorb and emulate from others, as you have to already know people's social positions before making the decisions.
Also, I don't recommend Heisig's Remembering the Kanji. I think Kanji in Context is a much faster, easier approach to fluency.
I do have significant doubts about what the site's author means by "fluency." The impression I get from reading his site is things like literature and poetry are a waste of time, and not considered prerequisites to fluency. Also, though he notes his Japanese was good enough to get him a job in Japan, he is working as a software programmer, and most Japanese companies require only minimal Japanese ability for those in software.
This is not intended to be a personal attack; I would only like to note that one must consider what it really means to be fluent before one talks about how easy or difficult it is to become so.