Thanks for posting such an interesting topic and discussion. I think we've all benefited from reflecting on this.
My two-cents first would acknowledge that I do believe the net presents a threat to the WTS at some level. The best "hard" evidence for me that the internet is effectivce is that it forced the WTS itself to get their own official webpage. I considered that a credible victory for the net and the anti-JW movement. As had been mentioned, the WTS seems to take the threat serious so they might have noted their own impact.
But let's go a step further and analyze what is it about the information on the net that would affect opinions about the WTS. I believe its the active negative presence of XJWs, not necessarily some individual logically analyzing the claims against false teachings of JWs. If I were to generalize the main issues, the anti-blood transfusion issue is a major one, combined with the backlash from the shunning policy of the WTS. Coming in close behind is the link between the WTS ans Freemasonry with the very publicized photo of the seeing-eye pyramid at Russell's grave site. I would include as a major factor COJ's work with chronology and a firm body of evidence against 607 BCE for the fall of Jerusalem, with pointers to 587 BCE. Certainly this is well documented and a focus of internet discussion. But when you look at the body of JWs as a whole, it is coubtful but one or two in any given congregation could even explain or knows about the fall of Jerusalem in connection with 1914. Witnesses "know" less now and simply feel they don't have to know anything, thus don't have to think or reason on anything, since all they have to do is look up what the WTS teaches on the matter. Even so, the presence of two articles about the fall of Jerusalem, leaning heavily on the work of Rofl Furuli, clearly indicates the impact these discussions have had on the public view of the WTS.
But also, just in passing, atheism and anti-Biblical information in general I think has an impact. There are some strong propaganda elements against believing the Bible at all, over an beyond a focus of some anti-JW groups. So definitely the internet has an effect, in general. Even so, it is good and interesting to see the figures. Thanks, again, for all your work on this data.
LS