On my X220 the Windows 7 boot is already fast even without a SSD (pre-desktop authentication and some Lenovo sauce helps) but watching the video FTA - that's mind bogglingly fast - it's more like the Mac's sleep/resume than a cold boot!
The key change seems to be a clever kernel session hibernation. They discard user sessions as those involve writing a lot of data (full hibernation) but save kernel session which can be written out and read back fairly quickly. Then there is multicore enabled resume - doesn't help with disk io but with decompression of hibernated data.