Interesting article but not really practical for most home networks simply because of cost. High-buck installations yes but not your average home. You're looking at buying a fairly upscale business class switch that supports VLANs and then bringing in a professional to configure it.
Some home devices support QOS but it really slows things down. However I do like using dual band wireless for exactly this reason. I run my bridges on the 5mhz band and my laptop on 2.4mhz. It segregates surfing from audio/video.
Unfortunately I have no idea how much bandwidth it actually takes to stream HD but it has to be less than USB 2.0's real world 20-25MB/s (160-200mb/s) because I can play BD rips just fine from a USB drive.
A better than average affordable small-office/home-office network attached storage device (NAS) might be able to transfer 30MB/s which translates into 240mb/s (bytes v bits) which will more than max out what 802.11N is capable of in the real world. On the other hand gigabit Ethernet should easily be able to handle twice that. Enough to max out the transfer capability of one NAS box and still allow a couple of people to surf the internet comfortably.
References:
NAS benchmarks
Real wold USB speeds
802.11N real world speeds