The good news is that a device with the same "RM-860" model has also been spotted in Nokia's NaviFirm database, kind of confirming its existence. Honestly speaking, this might be many things. It could be the rumored Nokia Catwalk (a PureView Phase II device like the Lumia 920), the Nokia EOS (a WP handset with a larger sensor like the 808), or a completely new device. (Not that the Catwalk or EOS are "old" devices.) Overall, most speculating sources reason that this might end up being a Verizon handset, but it may also be destined for AT&T, as that is where the EOS is expected to appear.
Whatever this RM-860 is, we'll probably know for sure at Nokia's event scheduled for February 25th.
source: OccasionalGamer via WindowsPhoneDaily