There are a lot of metrics for website traffic, unique visitors, user numbers, and the likes. Measuring a website's “influence” is a harder proposition though, it's not exactly something you can count. Some people beg to differ though and ://URLFAN aims to do just this, measure a website's influence by counting the number of mentions it gets on blogs. It's not the most objective metric out there, but it's probably as good as it gets and it's an interesting perspective.

The ReadWriteWeb blog put together a list of the top sites on the service and their standings a year ago. At this moment, despite the growing number of people predicting its demise, Wikipedia sits at the top as the most influential site on the planet. It's not much of a surprise this one, the crowd-sourced encyclopedia holds huge amounts of content and information which comes in handy when you're trying to put something in perspective or provide more background information.

Wikipedia is followed by YouTube and then Flickr, which have switched places since last year. Their presence is entirely expected, one being the most popular video site on the planet and the other being the most popular photo sharing site among bloggers, even if it's not the biggest in its category. Things only get interesting on fourth place where Twitter now resides up five places from last year. With the huge surge in popularity and users the microblogging site has seen this year, the rise is actually rather unspectacular, but the service was obviously a lot more popular with bloggers in 2008 than it was with the rest of the Internet population.

The other hyped up social media service of the moment, Facebook has also shot up quite a few places entering the top 10 at the seventh place. With 325 million users and a warmer attitude towards making content public, the social networking mammoth will probably only get more influential and it should be interesting to see how it will compete with Twitter in 2010. There certainly other ways of measuring online influence but ://URLFAN's is interesting as it puts more weight on people's opinions rather than just cold numbers.