Note: We’re back from holiday, digging out of email and catching up with news. 

Really good data on growth in social network traffic in the first half of 2008.  Inside Facebook carries results of recent comscore rankings. In short, Facebook and Hi5 are the fastest growing networks, while MySpace is less hot in terms of growth, although still a goliath.

What’s the nuance? 

During the first half of 2008, the market became increasingly concentrated amongst the 6 market leaders. Although uniques to the leading 6 social networking sites increased by 88 million, uniques to the other 276 social networking sites in the category actually fell by 24 million from December to June. Despite all the new social networks being launched, it’s proving to be really hard to gain traction at this point.