you can decide for yourself on how you define the 'end' or 'death' of a game. As far as i'm concerned, this game can't ever die due to the simple fact that you can always make new addons and host singleplayer or LAN based servers. What ever glory this game has ever seen has long since been gone years and years ago. The good memories are well cherished, but honestly it's good to move on.
This game outgrew itself in every way possible despite all odds, and was never truly intended to last as long as it has. The games date of release is probably the real culprit of its demise, it was essentially ahead of it's time. If retail caught the later sandbox / 'Minecraft' rush, had development decisions that were more thought out, and marketing was expanded beyond simple Google adsense we'd be somewhere else entirely.
It's good to let go and not get too attached to a LEGO styled building game lol. When I get that itch, I'll easily log on and build whatever it is I want, when I want to. I have my Auth key memorized and I always have a flash drive with different versions of Blockland on it. This game will always hold memories from a simpler, better part of my life, but at this point we are just beating a dead horse. It's embarrassing to even consider this game coming back into it's former glory.