I think OP don't know how to make a poll... The options are awful!!! Even if the game sucks it would still obviously last more than 1 year.
Seeing how there are already item stores selling ****tons of gold and items, bots farming gold and legit players bored as hell trying o farm items (I said farm, not actually finding it. Even farming in D3 is a disgrace) then I would bet that D3 won't hold its popularity for more than 2 years. And that because I didn't include the possibility of duping being possible in D3 to screw the game for good.
For me personally, it has lasted for 3 weeks. Barb in Inferno, just bored out of my mind. Alt+f4 after 5 mins of playing, just can't force myself to keep playing. Heck, don't want to force myself to play a game.
I think diablo 3 is the first game to have faced so many issues right from the launch. Problem after problem after problem. I'm still willing to bet it will last years but won't have as many dedicated members as it did for d2. Basically, a success with no real hardcore fanbase.
You have not played WoW in the first year, have you ?
This game will have a large audience for 3-5 years, then some hardcore players will stick around for another 2-3 after that. By that time there may be a Diablo 4 released, or another completely new franchise.
Despite what some people have said, how this game may be ruining Blizzard's reputation or alienating their fanbase -- you know that those same people will also be willing to try out a new franchise or a new Diablo game.