This blog's PersonRank seems to be based on the following formula: one point for every ten posts, occasionally reduced by one point (for some kind of indiscretion?).

so for >100 posts you get a PR of 10? I think I got mine before I had 100 posts...

Corsin, no-one currently has a PR of 10 with under 100 posts.

Everyone with 100+ posts has PR9 or PR10.
Everyone with 90-99 posts has PR9.
Everyone with 80-89 posts has PR8.
Everyone with 70-79 posts has PR7.
Everyone with 60-69 posts has PR6.
Everyone with 50-59 posts has PR5.
Everyone with 40-49 posts has PR4.
Everyone with 30-39 posts has PR3.
Everyone with 20-29 posts has PR2.
Everyone with <20 posts has PR1.

Source: http://blogoscoped.com/forum/personrank-full.html

the formula has changed over the months, so may have been different when corsin was >100 posts.
but there is more to the personrank formula than this anyway...

There are a couple of things making up PersonRank, but there's no complicated math involved... it aims to be a pretty straightforward indicator of how "regular" someone is here.

Oh heavens looking at that chart I am 4 posts from self destructing.

PersonRank looks for users IP?