The site owner Matti Nikki has collected addresses of blocked sites to his site only to show public that Police blacklists also sites that don't have child porn. Finnish police hasn't commented about why they censored the site. Electronic Frontier Finland has a press release in english about the subject.
One funny part of the law is that Finnish Internet service providers don't have to use the blacklist. Most ISPs use it because the public pressure is huge to join the censorship front to a good cause."