Search Engine Roundtable followed up its poll of Adsense Publisher earnings for 2007 from last week with a new poll asking if Google Adsense earnings were down in January 2008. Of 187 responses to date, 63% said their earnings were down. There are quite a few possible explanations - the one that comes to mind immediately is that there is much less competition for traffic in January than there is in December, when most are clamoring for visitors during the bustling online holiday shopping season.