I've been waiting for them to bring in ePIDs too, or should I say hoping it never gets to that point.  It might work for some people but not for others.

I've read that anything with a brand needs a UPC number so I leave the brands out of my item specifics and just put it in the description.  I don't know whether having the brand would make a difference (in item specifics) but I'll play it safe as long as I can.  When the day comes that I can't list without it, I'm out of here. I won't be the only one from my category who has no way of finding MPNs or UPCs or any other number.