No, I got the joke, I just didn't consider it very good.
Slashdot is odd. Most other places, jokes are considered good if they are clever, unexpected, witty, amusing, and most of all, ORIGINAL (around here, most jokes like that will offend someone's sacred cow and get modded as -1 Troll).
Here, jokes are most likely to be enjoyed, encountered, and/or modded up to +5 Funny if they are repetitive, predictable, expected, tiresome memes.
This pattern is so consistent and observable that I think a conclusion about it can be made: slashdot is filled with insecure (and perceived or real) outcasts who have a certain desperation to feel like they fit into a culture of likeminded people. If you view it that way, suddenly the irrational celebration of the ten millionth "sharks with lasers on their heads" joke makes sense. If you view it that way, the hostility they often show when you reject or even question their brand of humor also makes sense.
It's sort of like when you were in high school and the more "average" people suddenly adopted the mannerisms, gestures, and speech patterns of the latest big movie or TV show, all the time pretending that they have always expressed themselves that way. The terror of being an individual! No meme is too repetitive, no joke too lame if it offers even a phony escape from that!