Strange disconnect from Topix investors?

TechCrunch reports that news aggregator Topix is to launch classifieds from six content partners - Eventful, Zap2It, Livedeal, InfoUSA, Apartments.com and Informa Research. Which looks to me a slightly odd list. Topix has investment from Gannett, McClatchy and Tribune, three of the five also behind Classified Ventures and three of the four behind CareerBuilder. And yet only one of the six cited sources - Apartments.com - is a Classified Ventures business (which incidentally may or may not work well alongside the existing property listings deal announcedin April with Trulia) and one of the others - Zap2It - operated by Tribune. I wonder what happened to Cars.com, CareerBuilder et al?

(HT: Journalism.co.uk)