Sera Gamble assures fans that there may very well be some life after death for Bobby. As she told EW, the question posed by the reaper in Episode 10 has still not been answered, and that opens the possibility for us, and the boys, to see Bobby again:
“That was the offer put to him by the reaper. ‘Come with me and be done, or stay here and be a ghost and face the consequences.’ So one of the questions we are left with is, ‘Did Bobby move on or didn’t he?’ The great thing about the show is none of these options preclude seeing Jim Beaver again at some point down the line. We can always flash back to an earlier time in their lives, we can send them to Heaven at some point, or we can say that he made the morally ambiguous decision and became a ghost and we can explore those consequences.”
But for the time being, Gamble wanted the boys to go through the grieving process:
"We really want to play with expectations for a while and explore what’s going on with Sam and Dean in their grieving process, [complete with] emotional fallout. But they must be wondering the same thing we are: ‘Did he move on? Is he still with us?’ I think grieving for them is not that much different than grieving for the fans.”
With Jim Beaver booked for a long guest stint on Justified, when, and in what form, do you think we'll be seeing Bobby again?