How did I made a page rank 3 site within 2 months

It's an automatic blogging site (using WordPress but on a standalong hosting), one blog post generated from mySQL database everyday - fresh content.

It's part of a mini site network of 4 sites.

It has got "all in one seo pack 1.4.6.13" installed.

It has got 3 paid links: 2 on page rank 3 sites and one on a page rank 1 site. (who says google doesn't like paid links?)

It also has got a few links from blog comments.

That all I can come up with. Any comments?