How many people in the world have Internet?   
A. 350 million  when new TV  season starts.
B. 1 Billion on the week end.
C. Anybody with electric power.
For a more ACCURATE ANSWER, Click on this image.
http://www.internetworldstats.com/images/world2012number.pie.png
Are you suppressed? The report was ISSUED earlier.
Here is a more up to date  stat.
http://internetstatstoday.com/
From the above site you will see that it is hard to know for sure how many there are. They hope to have full data  sometime this year.

Last year it was maybe worldwide 4.3 billion users. But that number is inflated. The real number is not yet known.Lots, give or take a few.Some people who have internet, have access to internet, but do not have their own connection from home.

The value is one that is always changing.

- You have people who have their own paid monthly ISP service
- You have the people who are tapped in on the NEIGHBORS open wifi claiming that as their own internet access.
- You have the people who refuse to pay for it and use wifi hot spots instead
- You have people in some countries where internet access is renting time on a computer by which they do not own, but they have accounts with a web IDENTITY, maybe even multiple identities for the same user.

Trying to figure out the exact count is one that is complex and ever changing. I cant think of any easy way to figure out the exact value. There is no unique identifier that can be used to create an exact count that is everchanging.