As a public posting, the blog is available to anyone that manages to find it. Hence, everyone has the opportunity to read the blog. This means there is a total blending of potential audiences. If you want to say something that you'd rather your parents not overhear, then you will need to disable their browser function, implant a worm that prevents certain website urls from being loaded, or install Net Nanny on their computer without telling them. Otherwise they are among the most likely candidates to actually read whatever mixture of alphabet characters you are typing into the "New Post" window.
Old girl friends and boy friends could be reading your blog. As well as friends from work (that weren't supposed to know about the ahem... er... hobby. Your children, distant relatives, friends of friends, strangers from any and every part of the world. Basically everyone. Not everyone individually. Everyone all at once.
Since everyone is reading the same blog you can't tell the tale a little different depending upon the audience. You can't use the politically correct version at church, the risque version with the boys in the locker room, the well enunciated grammatically correct version for the management team at work, the "honey you know I would never do that" for the misses. It is all the same version for everyone.
You can't blog about winning the lottery when you are still playing duck and hide from the neighbor down the street that lent you the money you don't want to pay back just yet.
You can't talk about the great golf score when the only reason you could get away from the weekend yard work was a little white lie about being totally disabled and needing to soak in the sports sauna at the gym.
It is the same version for everyone.
However, you don't really know who specifically is reading any particular blog. Granted, you can count your followers. But you don't know if they happen to read a specific blog. So, you can't rely upon them having read anything in particular.
In practical terms that would mean that if you post an invite to a lawn party in your blog, you will still need to personally invite everyone you actually want to make sure know about the event. It's worse than email. With email you have no guarantee but you do have a vague notion that the content made it to their inbox (except for the ever present spam box and internet glitches). With a blog you don't even have the imaginary certainty that the content made it to their inbox. They may or may not have even glanced at the page -- let alone actually have read it.
So, in a strange way, even though may people can read the blog it is no one at all -- at least no one in particular.
The only folks that you can know have read the blog are those that comment. And since a mircoscopic percentage of readers actually comment that means in general you can't know, which means in general you are typing to no one at all.
I have developed a simulation of this designed to give a peek into the dynamics of this for anyone curious about the inner effects this type of communication.
I invite psychologists and anyone studying social dynamics to try this out.
Blogging Simulation 101
Set up a room with standard lecture seating.
Have each individual present take a turn telling a joke or story. The joke or story should be two or three minutes long.
As they tell their joke everyone in the audience is sitting with a cloth bag over their head. This should allow them to see out, but not display their expression -- or even whether or not the eyes are open. The members of the audience say nothing, do nothing, make no action that would reveal whether they are listening or not. They could be listening or totally ignoring the speaker.
After each person has taken a turn then discuss the results.
Report back if you dare.