Oh, I know this one - they'd all run away and keep trying to convince themselves it's a dream.
And yes, I'm being serious. That's pretty much the normal human reaction, at least as far as I've noticed. 
"If I had Force powers, vacuum or not my cape/clothes/hair would always be blowing in the Dramatic Wind." - Tenzhi
Characters
You don't think any of them would stop and stare in wondrous amazement ?
Hm, point. The guys with knives might not be scary enough to make them run right away. Everything that I'm talking about was enough to illicit an immediate panic response, so I guess my data might be kind of skewed there. 
"If I had Force powers, vacuum or not my cape/clothes/hair would always be blowing in the Dramatic Wind." - Tenzhi
Characters
Uhm... I'd say that B) would wind up tied to a second post as she tried to 'intervene peacefully'. Dunno if she'd be sane at the end of it or not, but I'm pretty sure she'd be quite dead.
A), if armed, would likely go in guns blazing. If not armed, he might just get himself killed trying to save the girl, or, conversely, he might just run away.
C) would either call the cops and march up to them and demand they release the girl tied to the post (and wind up tied to a second post, just like B)), or brush on past because she has more important things to do.
D)... eh, hard to say. He might intervene (and get killed), he might just run- of the four mentioned, he'd probably be the most willing to accept Cthulhu-on-the-bay as more than just a chance cloud formation, or he might call for the police.
I doubt any of them would acknowledge the cloudy-looking Cthulhu as real unless forced to. Modern (western) humanity is distinctly less than fond of any implication of the supernatural imposing itself on their lives. We don't like the idea of something more powerful than mankind taking an interest in us for any reason.
"A soft answer turneth away wrath. Once wrath is looking the other way, shoot it in the head." Seven Habits of Highly Effective Pirates
MA Arcs: #12285, "Small Fears", #106553, "Trollbane", #12669, "How to Survive a Robot Uprising"
A) Insane, but strangely happy
B) Sacrificed as well.
C) Insane with new psychosis. Now she thinks little green men are in her teeth.
D) Strangely sane. The Ch'Thuloids are a product of American literature, not actual mythos, this creature has no actual power over him or reality. To him, this is all an illusion.
Unless of course, the reaction is to the actual picture, and not in context.
Then it's
A) "Aw, cool!"
B) "Oh dear..."
C) "Hmph."
D) "Hm... Interesting picture."
My Stories
Look at that. A full-grown woman pulling off pigtails. Her crazy is off the charts.
OK, I think I have gotten the information I needed even though only a couple of you responded. Thank you for your input.
Thank you Mr. Grey. That is more along the lines of the type of answer I was interested in. My original question had nothing to do with the various mental states of my fellow forum goers but whether or not the passive effects in Lovecaft's writing would have the same effect on the minds of modern people as they supposedly did to his Edwardian characters.
Personally I do not feel they would. My opinion is that confronted with such situations, todays peoples ......... I was about to write "from 1st world culture/counties" but then I realized there are several scenarios where in 3rd world people would have no problems dealing with such things while everyday suburbanites actually would start foaming at the mouth and gibbering. So with that in mind let me further define the scope of or test subjects.
A) Joe: mild manners shopping store casher and hard core gamer boy. No car but 4 different console systems, water-cooled quad-chipped over-clocked comp with a T-3 hardline.
B) Mindy: Free-spirit, vegan, thinks all aliens highly evolved peaceful people, volunteers in an animal shelter and makes her own clothes in protest of the sweatshops of the world.
C) Janet: Mindy's opposite. Suit wearing, Lexus driving, corporate cog and happy because she KNOWS she is going to be a success (just ask her therapist).
D) Proshottam: Grew up in India and has moved to the "West". Window washer currently but learning to be an IT Specialist.
Was going to add a few more but realized my actual knowledge of other cultures is full of horse apples and I did not want to offend anyone in said cultures. So going with the very small sampling here how do you think these people would respond to say this scene.