Just because they're not here to see certain posts doesn't mean they wont be someday. Also, you shouldn't talk about people behind their back. If you don't have anything nice to say, please don't say anything at all. Would you do this to others as well? Or just anyone out there you can find?
I don't find that to be quite funny to be honest.
Some of those people were among the first on the forum and I don't think they'll appreciate you making a huge joke out of something, true they're gone for a [good or bad] reason, but that doesn't entitle you to that.