I know this is not what the article talks about, but ... Bellard did this in 15 seconds, in 2004 with a 2.4Ghz Pentium 4. In the 7 years since, I except a 4-fold increase in speed, so on modern hardware it will probably be 4 seconds, maybe 1 or 2 on the beast described in this article.
The base kernel is not a lot bigger. There are about four times as many drivers. (But bellard's compilation only included the ones needed, IIRC. google tccboot for more info)
