Forgot something?
While I understand the need for some noise on the helicarrier, the sound you chose sounded more like static. Maybe something with a bit more of a fan-like noise. The footsteps used aren't that great. I know you're going for a metal feel, but that the sound belongs to a tiny metal catwalk, not a solid floor. It gets deeper later, but still sounds more like thin metal grating.
Spider-man's voice actor sounds great for him, but Fury's sounds more like Morgan Freeman than Samuel Jackson. (Which isn't bad, just an observation.) Black Widow's actress needs a better mic, but the only reason it stands out is because of the others being so good.
The slide transition took me out of the short, and a fade, or even a simple cut would have been a more fitting choice.
The zoom out with Spidey at the window was executed well. The mouth animation is nice, and the eyebrow is a great touch. I like the spider-sense, it's simple, subtle, and works well. The effects are generally good, with just a couple of rough spots.
Plot-wise, it sets up a larger world, and does a good job at hinting at bigger things. There's a big problem though, it ended....Without an ending. Not titles, no credits, no finishing of the last sentence, not even a "To be continued" slide. I'm guessing that was due to a render issue, right? Anyway, it's a good start, but just be sure to keep that quality up.
Of course, there are a few issues. Because the Spider-sense goes off right as Hawkeye and BW walk in, it leads people to think that they are the cause of it. Then Hawkeye's grumpiness and horrible shot go further to prove that theory. If you didn't want us to know, you should have made it more subtle, but as is, the hints don't pay off...At least not yet. Also, an entire HUGE airlock can be opened with one arrow? Might have been better to have Venom reach over, pull the whole control panel out, and then have the door open.
The animation was surprisingly good, but could use a bit more easing at times.
Good job, can't wait for the next one!