I wonder if it's possible to increase the speeds, without having to revise the chip-on-the-motherboard. Then users could upgrade their speeds by buying a new "faster" cable.

It looks like that's what they're doing (unless I misinterpreted this quote):

> Our telecom source noted that Intel made an unusual choice in also using active cabling for future optical-based iterations of Thunderbolt. Passive cabling is more common, but active cabling could offer some advantages. For one, active cables could combine fiber optics with electrical cabling for power transmission. Another good reason to use active optical cables, according to our source, "is that your current electrical ports can be forward compatible with future optical cables."

Those future optical cables won't be faster. Some people are optimistically misinterpreting Intel and thinking that they'll get 100 Gbps out of existing Thunderbolt ports, which is definitely not true — those ports are already going as fast as they can. Optical only gives you longer distance.

The chips are doing some kind of signal conditioning; they're hardly NICs.

If I had to make an analog to any kind of networking device, it'd probably be a MAU, or possibly an AUI+MAU. https://secure.wikimedia.org/wikipedia/en/wiki/Medium_Attach...