and did you bother see the video ?
No I have to say I did not watch the video. I have been tethering with both the S2 and S3 on IQ260 since late 2013, first on the S2 and then S3. Stayed with the S2 due to reasons I preferred.
If the video is showing the S4, then it's not anything new. I have seen the spec's. A bit more power and larger screen. May be possible to have a more laptop like feel, but the larger it gets the less ideal IMO it is for tethering in the field.
So far as I know, the S2 and S3, all have a removeable keyboard, the S3's is much better for daily use with a better touch feel for typing. However I find the S3 is just a bit big for tethering in the field and prefer the size of the S2 even with the extra weight.
My point is this just a continuance to a long line up of Surface products and tethering with them has been done since the first model, albeit it was not a good answer as it did not run a full version of the OS.
My other point is no single person besides Ken Doo has done more work on this subject. Ken has made all of his findings available to anyone and has shared all of the pros and cons of each solution. Ken has worked this solution to near brilliance with the last version and his notes are well worth the time to read. Just want to give credit where it's due.
Paul