I have to agree with Gregor, the watchtower is on a decline that will get greater particularly as we approach 2014. Since it will be 100 years since the society has been teaching christ presences, many people will just fade away out of a combination of frustration and disappointment.
The wit messes have structured there system uniquely differently then other corporations and are not subject to the same things that effect different companies.
Although the WT is unique, it also has unique vulnerabilities, one being it's history and current false expectations. In Rutherford's time, many left after his false predictions. Today because of the internet, more and more people are being informed about the societies missteps, they can no longer hide it. I really think the cult religion it will become more marginalized in the next 10 years. You will always have a small group of hardcore Jdubs but hey, even scientology has it's hardcores.