Friend of mine said something about the mechanical web-shooters that I definitely agree with:
"The web-shooters decision is fine in theory, since it goes back to the source comic while also giving this movie a huge difference from Raimi’s trilogy. In practice, however, it makes no goddamn sense. We’re explicitly shown that the synthetic webbing is being produced by genetically engineered spiders, and it’s one of these spiders that bites Peter. Given this context, why the hell wouldn’t Peter be able to make the stuff himself? Furthermore, this means that Peter has to order his web cartridges directly from the manufacturer. It’s hard to believe that this stuff would be available for commercial purchase, and harder still to believe that one teenager could order whole crates of it without anyone raising a red flag. Moreover, the knowledge that this webbing could be so easily obtained by anyone in the world makes it a lot less special. If Peter could order whole crates of webbing and make a shooter out of scraps, what’s to stop some other industrious guy from doing the same? God forbid, someone else could figure it out, post a how-to video on YouTube, and we’ve suddenly got a whole nation of webslingers!"
Here's the whole review if anyone's interested: http://moviecuriosities.fmuk.org.uk/?p=3454
He's probably modified it. He says he developed it himself. I just wonder if it's as biodegradable as it is in the comic books, or if Spidey is leaving strands of webbing all over the place. And watching this new movie, I'm realizing for the first time how many car accidents he'd cause swinging around busy city streets like that all the time.