I don't believe it.
Everything I have ever plugged the phone into/bench mark tools are telling me its a 3630, including RSD Lite. Nothing has ever told me its a 3610.
My personal opinion, is that Motorola don't want to advertise that it has this CPU as the phone is much cheaper than its "higher end" models and they don't want everyone going out and buying the defy over say the Droid X or Droid 2.
Whatever its got the bench mark results of this phone are awsome - and its on 2.1.
Nexus 5 - Cataclysm - Faux Kernel (of course)