The other day when Apple announced its latest MacBook Pro releases, Intel also officially released ThunderBolt, the new cable connection option that puts USB and FireWire to shame with upto 10GBbps speeds.

Thunderbolt is a 10Gbit/s, bi-directional, dual channel, copper link containing an Intel controller chip and supporting two protocols: DisplayPort and PCIe. Intel says a high-definition movie can be transferred across it in less than 30 seconds
But what happened to LightPeak? Intel's original name for the project was changed when PC manufacturers demanded a cheaper, non-optical option. Intel caved to pressure and replaced its fiber-optics based LightPeak to an electrical version, and renamed it Thunderbolt.

The rub is that the current Thunderbolt technology - which debuted today on Apple Mac Pros – only works across a 3 metre cable. But according to Yogec and Ziller, Intel will eventually offer an optical cable that will plug into the existing on-system hardware, transferring data across much larger distances....And eventually, the company says, it hopes to introduce an all-optical setup, where that optical transceiver sits on the PC.

According to Intel, the electrical version of the technology provides exactly the same speed as the optical version. The only difference is the length of the cable – and cost.
Quotes were provided from The Register articles.