Yes it is. And hopefully with some of the features that have been requested, something more automated can be set in place. We have a shop system idea that would be really awesome, that could do this. They can buy a custom greeting for x points.
But if you just want a welcome back message, then I suppose that could be done to. Might be able to be done now, depending on if I can do a custom command that viewers can enter themselves. I will test and see if I can, and let you know.