Since I was not familiar with the term "Vision Mixer" I found this in Wikipedia.

"The terms vision mixer and video mixer that describes both the equipment and the device operator are used outside the USA. In the United States, the equipment is called a video production switcher and the device operator is known as a technical director (TD) that is part of a television crew."

I then found this:

"Most vision mixers are targeted at the professional market, with newer analog models having component video connections and digital ones using Serial Digital Interface (SDI)."

SDI for 1080p;

"An emerging interface, commonly known in the industry as dual link HD-SDI and consisting essentially of a pair of SMPTE 292M links, is standardized in SMPTE 372M; this provides a nominal 2.970 Gbit/s interface used in applications (such as digital cinema or HDTV 1080P) that require greater fidelity and resolution than standard HDTV can provide. A more recent interface, 3G-SDI, consisting of a single 2.970 Gbit/s serial link, is standardized in SMPTE 424M that will replace the dual link HD-SDI."

First of all you better find out what signal you will be fed from your "Vision Mixer", as you can see without that specification and assuming that there is no compression codec inside the mixer you have a major bandwidth problem.  There is no way that firewire could handle 1080p without some form of compression.  You might get a third party HD-SDI to Firewire compressor but I do not know how that then would affect your workflow.  Also Firewire is on its way out

Does your laptop have USB3 or an Express card slot? Does your camera have HDMI or SDI?

Eric

ADK

The Blackmagic Intensity Shuttle would be fine for the I/O device if you can go HDMI from the Mixer or via a converter in between. However keep in mind Component will only carry Interlaced. You don't want to convert component unless the converter also De-interlaces. If HDMI is not an option then you will need SDI and a different Blackmagic device. Since you are delivering to Web you may want to consider the Matrox MXO2 series instead of the Blackmagic since you have the express card slot. Which ever one you decide on, you can use their utility to capture the material into the Blackmagic or Matrox codecs and then import it into any editor to quickly cut and upload. You may also want to look at Wirecast Pro by Telestream. They have capture options and work with the Blackmagic hardware. Wirecast Pro will also allow you to broadcast live via Web and gives you some further mix/key options.

Eric

ADK