Investors and blog commenters suffering Internet-induced infantilism thought Apple was phoning it in with its Tuesday release of its 4s model. Five days later, all pre-orders for the iPhone 4s were sold out.

Cambridge Day is part of a project called Voices of MainStreet — a weekly, nationwide Q&A in which editors at the money and lifestyle site MainStreet.com ask questions and bloggers answer them. For this entry, we were again allowed to choose our own topic.

High-tech gadgets such as iPhones aren’t cheap and, although the way we use them is supposed to be feel simple, of course they’re extraordinarily complicated, reflecting millions of dollars and hours in research, design and manufacturing. What’s weird is when we get evidence that the more people know and care about this pricey complexity, the more childishly they behave about it.

If you were watching or taking part in the live blogs Tuesday about the launch of the Apple iPhone 4s, you might think the world was coming to an end, mainly because many people weren’t expecting an iPhone 4s, but an iPhone 5.

“I’M NOT BUYING THE IPHONE 4GS. WHAT A SCAM!!” said a participant in TheStreet’s live blog named bobs big boy, hitting the trifecta of Internet commenting: getting the details wrong (It’s not the 4gs, it’s the 4s); accusing everyone and everything of being a fraud (even though rumors of an iPhone 5 were conjecture and wishful thinking, not things Apple promised and failed to deliver); and delivering apocalyptic pronouncements in earth-shaking, world-shattering ALL CAPS.

“FAIL!!! I’m going to Verizon now and buying 4 droids with 4G and selling my apple stuff!” said Warhero1, ramping down the all-caps but adding an exclamation mark and more tantrum by not just refusing to buy an iPhone 4s but actually threatening to go to Verizon to buy four(!) competing phones. (I shouldn’t make fun. I was so disappointed that the latest Audi A8 didn’t give drivers the power of flight, although Audi never said it would, that I went to a local Ford dealer and bought four Fiestas. Take that, Audi!)

There were, of course, some reasonable voices, such as TheStreet commenter Gene Hancock, who said, “Call it what you will, it is a new phone!”

Indeed, the 4s improves the phone’s camera, adds video capabilities, institutes an operating system with some 200 new features and a file-sharing system called iCloud, brings a new, faster microchip that also adds battery life and better graphics, claims to enhance call quality by switching between antennae to send and receive signals, lets people use the same phone while traveling overseas and, most amazing of all, introduces a voice-activated system called Siri that seems to do just about anything you want by interpreting what you tell it. As Wired’s live blog put it:

You can ask Siri about stocks. Siri says, “Nasdaq composite is down right now.” Siri is also partnered with Yelp, so you can ask something like “Find me a great Greek restaurant in Palo Alto.” Siri responds, “I’ve found 14 Greek restaurants; five of them are in Palo Alto. I’ve sorted them by rating.” The ranked listing follows below … You can also ask Siri Maps-related questions, and it will read you the directions … If you get a message, and your phone is in your pocket, you can ask Siri to read it to you, hands free. You just have to say, “Read my message.” Siri reads the message, and asks if you want to “reply” or “read it again.” You can also ask it questions about your calendar … You can also set up meetings hands free … Web search is also integrated with Siri. So if you’re looking up info on the space program, you can tell Siri to “Search Wikipedia for Neil Armstrong.” The relevant Wikipedia page comes up in Safari almost instantly. Siri is also partnered with Wolfram Alpha … You can ask Siri to “define mitosis” and a definition comes up … Traveling abroad? Siri finds the current exchange rates, so you can see how many euros to a dollar, for instance … If you’re counting down to a special event, you can ask Siri. How many days until Christmas? 82 days (or 2 months, 21 days; 11 weeks, 5 days; 58 weekdays; .22 years) … Siri can also play any song you want, if it’s in iCloud or on the device …

Yes, I know, so dull and disappointing. TheStreet’s Robert Holmes wondered if “perhaps the company should have waited and saved new CEO Tim Cook from the embarrassment of trying to sell consumers on the underwhelming iPhone 4S … essentially the same phone they already have,” and at the announcement of a 4s instead of an iPhone 5, shares of Apple stock lurched down $20, to $355 a share, then ended the day down only $2.10 a share. Trading ended for the week with Apple down $7.57 a share, to $369.80.

Fast-forward to Sunday, as carriers announce that the staggeringly disappointing 4s, which is due Oct. 14, has sold out its pre-orders — although AT&T’s announcement alone puts the new iPhone on track to be the fastest-selling Apple device in history.

Trading opens today with that for investors to chew over, and for folks such as bobs big boy and Warhero1 to teethe with. Anyone that disappointed in the 4s rollout should get real, and learn to appreciate a reality that brings Siri to life in a gadget that fits in your pocket … no matter what that gadget is called.