Google can't open source Google Reader even if it wanted to because, to make connections and recommendations it used Google's Crawler which is part of the rest

Google can't open source Google Reader even if it wanted to because, to make connections and recommendations it used Google's Crawler which is part of the rest of Google's infastructure - something which Google definitely won't open source. As well as using Google's Crawler, the Google Reader team created separate recommendations to improve Google Reader and those people don't come cheap either - and giving up that knowledge is valuable to Google's competitors.