Is it not Link Farming?

I know a site which ranks #1 on Google with VERY competitive keyword in Japan.

Actually, the keyword (keyphrase) is SEO related.It is the most competitive keyword in Japanese SEO market, since just the word "SEO" shows a lot of English sites as well on Google and they don't want that.

Anyway, the site owner actually speaks out what he did!
And it seems to me a "link farming".

What he says is he made 100 or so blogs (Free hosting). And he linked all the blogs each other so that they have backlinks themselves too.
Most of the blogs are about SEO, and some are not.

And from those blogs, he linked to his main site with anchor text.

I checked his backlinks through Yahoo Siteexplore, and he has only 2000 or so backlinks.While his rival sites (of course big SEO companies) have at least 10,000 backlinks!!

He also has backlinks from social bookmarking sites, some blog commenting , directories etc, however, most backlinks are coming from his own blogs.

He constantly updates his blogs, and he says this is for make the blogs "fresh" and Google and Yahoo likes "fresh" sites. (This seems quite a lot of work, updating 100 blogs quite often though).

Anyway, it does not seem temporary, his site has been on #1 for 4 months, and he says it had been #2 for 2 months before it got #1.
So, it has been ranked high quite a while!!

And surprisingly, he started it 8 months ago.It means his new site got #2 in 2 months. (You can confirm that his blogs started last October.)

Anyway....
My question is, isn't this link farming?
Why does google NOT do something about it?
The guy says "Google only cares about much larger scale link farming and doesn't care about only 100 sites or so."

Do you agree? Or is he doing something very risky?

Oh by the way, you might wonder if those blogs have their own backlinks.
Most of them have backlinks from his own blogs and not from somewhere else. Their page ranks are mostly 2-3.

It is his strategy but he officially speaks about it on his blog.