Opening shot - draw a circle around a guys face.
What is this? Is this a security check? Or were they just trying to highlight that guy for no apparent reason? I'll remove that.
Second move -
List of boxes in an order you set with all sorts of stuff going on in them. There is a hideous amount of wasted space here, why do all of these things need different boxes? For those messages, what is wrong with having a notification on a taskbar saying you have an unread message? It's a waste of space. I'll remove that.
Clicking on paragliding video -
Wheres the middle step? What if I don't want to watch a paragliding video? How is this any better than having a desktop shortcut to a video folder? I'll remove that.
Vague social networking/Nasdaq shot
People/What's new/ Me is all very well and good if you can integrate Facebook, where everyone is actually updating. Last time I used an MS social network was by accident when I checked an old hotmail account to get some very old login details and windows live showed me the 4 updates from one person in the past 3 years on the Live network. Even if you can integrate working social networks, it looks like a crappy way of interacting with that network, I'll remove that.
Games
Sure many people will welcome interaction with Xbox live and as an Xbox gamer myself I'm all for spending hours playing Skyrim. But I can get all of that info every time I turn on my Xbox. My Xbox is where I'll go for that information. If it's an integration of PC and Xbox gaming then crack on, I won't use it as I don't use a PC for gaming much above humble bundles. I'll remove that.
Photos
Ah it seems you have developed a way of sharing photos. Shouldn't find too much competition there. As it is my phone automatically uploads all of my photos to G+ where I can then share them straight away. I'll be removing that. (I think all of the exclamation marks here are a sign of the target audience.)
Where are we meeting?
I travel a fair amount for work, I have never had to google coffee to find a nearby place to meet a colleague. Day to day, this won't be used because people know where they meet, they met there last week and the week before that. If I was in that situation 10 minutes time I would do the following. Windows + R - www.google.com - my location/what I want to do. This doesn't seem like any more work than the Windows 8 guy is doing and if I was in an IM with anyone It'd be in google chat anyway and I'd be much closer to google maps because of that. I'd also be on Chrome, a browser I chose because I don't trust MS's not to completely bone every computer on my home network. I won't be using this.
Opening Files
Unless the trick here is that Windows 8 magically picked out the various files this guy needed for this meeting, there is no trick here at all. All you are displaying is a system to look at the files you have. Stop the press. I'll be keeping that in, because I need it and expect it to be there. It is to me essentially what an OS is. If you could do away with the flashy opening and minimising stuff that'd be great (you too, OSX).
Closing Shot
3 lovely devices all running an operating system designed to work on only one of those devices.
There is a very good reason this video is so fast paced, it's to stop you from actually thinking about what's happening on the screen at any moment and realising it's all been done before or is pointless.
TLDR - Windows 8 - SHINY! FAST! COLOURFUL!