I agree that most only find the "apostate" websites AFTER they have already come to have serious doubts regarding the Organisation's claims and teachings. That the percentage of those DF'd for "apostasy" may seem unchanged (even if accurate [which I doubt]) does not take into consideration faders, nor those who are already secretly "apostate" (per WTS definition), but who are now caught in a moral lapse and officially ousted for reasons other than "Apostasy". The fact that the numbers of new converts in nations which are heavily internet-connected appear to be nearly uniformly DOWN suggests that the internet is having a significant effect on recruitment, which will bear its fruit over the long run.
I think it is also important to consider the effect on the "walk-away believers". In the past, many who left because of the stress of the Witness lifestyle, or the lack of love in the congregations, continued to believe that the Organisation was nevertheless correct. Even those who had been DF'd often felt they had been rightfully expelled (AKA "penance syndrome") and would sometimes encourage other individuals on the fringes of the Organisation to remain with the WTS. "I know it's the right religion, and someday I'll return; I just have to get some things straightened out first..." (I personally know some who engaged in informal witnessing while outside the fold.) No longer. Now once they're outside, they find it as an opportunity to investigate various facets of the religion, and those who do NEVER (TRULY) return. Furthermore, walk-away believers seldom had reason to be very vocal, even about such things as the shunning. Many "apostates" today may not be screaming it from the rooftops, but they are fighting to get their relatives and friends out. And the Internet has given them the ammunition to do so.
Perhaps the Internet may appear to be having only a small impact, but it is achieving results on a number of fronts, and the effects are beginning to "snowball".