no, d2 isn't dieing. its too unique of a game. it combines mmorpg-ish style multiplayer almost, with semi-interesting action, with the massive clicking of some fps's.
it might be because your on west. i know from experience that many people usually switch over to east. no idea why... i switched when east was less populated... and therefore less people = less lag, and i've just stuck with it.
the game making line is nothing. its almost hit 2000 for me on east once or twice, but if i wait about a minute, its gone.
the only REAL thing that would cause d2 to die, would be the massive botting. simply because it allows almost anyone instant access to all the best items. mh isn't as bad as most people think, and if you really can hack into b.net, you might as well **** around. luckyily for bots, the makers are starting to charge for them i believe, so that cuts back on it a bit. and even then, alot of people dont bot. so in reality, botting isn't much of a problem either. d2 will REALLY die, once we get 1.09d hacked/bugged items back, like hex's and the shit. and even then, blizz will just slap us with another patch. probably without any balance changes on it, just some code to destroy all the hacked/bugged items. *shrug* ida know
but no, d2 isn't dieing. and even when it gets boring, play some other game. then come back to d2, it i'll be fun again. there are almost limitless possibilites for characters, plus there are dozens of kickass mods that make it even more fun after all of that.