I will keep my nano, but instead of buying an iPod video, vPod, whatever new, mostly useless device that comes out, I'll probably be getting a Zune, or holding onto my nano for awhile more. It plays music and that's all I really care about. The only time I'd watch videos is at the gym, in which case, the ability to flip the screen and use different video formats is a plus for me. Same reason I was considering the creative vision:M but creative's software bites the big one. If Zune can offer me better, then Zune it is.
The only iPod that could persuade me to stay is a Product (RED) video device, simply because I support the cause and brand awareness of product red more than I care about the iPod versus whatever else debate. If they drop one tomorrow as rumored, then there is less of a question in my mind.