Colin Green "tweeted" me earlier today to make me aware of his (excellent) response to Richard Carrier's article, "Origen, Eusebius and the Accidental Interpolation in Josephus, Jewish Antiquities 20.200" published in the Journal of Early Christian Studies, Winter 2012, vol. 20, No. 4. Colin's article can be found here:
A review of Richard Carrier's journal article on Origen, Eusebius, and Josephus