In
changeset 1048 I've enabled PTP support by default for the cameras that were reported working in the PTP thread, and those that already had it enabled in camera.h
These are a540, a590, a610, a720, d10, ixus870_sd880, ixus970_sd890, ixus95_sd1200, s5is, sx200is, sx20, sx30, g12