1: The internet has already impacted the decline of religion. Any kind of access to more information, more viewpoints, will change the dynamics of what people believe. If you're surrounded by like-minded people and aren't introduced to other ideas, of course you're going to believe what they believe. There's a reason that Christians have Christian children and Hindus have Hindu children, and that those are prevalent in specific societies; it's a tradition passed down by blood and community.
2: I've always been an atheist, but the internet has allowed me to speak with other atheists (something that simply doesn't occur for me in "real life" as my family and most people I know are religious).
3: I know a couple of people whose minds have been opened through exposure to competing ideas, though they haven't necessarily shed all of their religious beliefs yet. It all starts with seeing that the world is bigger than you were led to believe, and questioning your assumptions.
4: Mostly all. I don't really know real-life atheists, except maybe one or two extended family members.
There is plenty of internet sites that preach religion, like catholic.com
There is a decline in religion in this country, but not in the world. It seems like when religion declines in one part of the world it gets bigger in another. Like in the 1500's protestants started in Europe at the same time 25 million hispanics converted because of the picture from Our Lady of Guadalupe.
Africa and the Philippines has become much more religious in recent years.
There is little evidence of Religion increasing in any of the educated nations, it is decreasing in every highly educated country on earth.
Simply because knowledge is beating Delusion, and showing that religion is just that.
It's only underprivileged and religiously enslaved nations like Islamic nations where there is any evidence of a slight increase in religiosity. But only slight.
Even in Islamic nations, the well educated are moving away from Islam, but they have to do it quietly and secretively under fear of torture and death, because religion is a murderous Ass, even Christianity according to it's own history.
That is why the US founding fathers were Deists and decreed the US to be a Secular nation, because of the stupidity and barbarity they saw religion producing in Europe.
This came from their own words.
Religious Delusion is indeed shrinking, the world over.
Hopefully we will be rid of or cured of this disease someday soon.