The article arrtibutes this happening because Google began promoting Google BlogSearch on the Google home page. One thing that is for certain, when you take a look at the chart they offer on market share of US search traffic, there is a huge spike in the Google BlogSearch numbers right around October 14th, 2006, when Google BlogSearch’s market share triples overnight.
To be fair, there is not enough data yet to say that Technorati’s traffic is declining. Only the last 2 weeks of the data shown indicate a decline, and that is not enough data to base a conclusion on. But, it is clear that Google’s traffic has leapt up.
It’s also interesting to think about Technorati’s exit options. An acquisition by someone looking to establish a major presence in the blogosphere seems the most likely option to me. Someone like Yahoo! could scoop them up and get a jump start into the space. In addition, this would provide additional ways of promoting Technorati that would increase the likelihood of their gaining market share in the future.