Like I said, maybe PvP will be awesome and people will remain hooked, but, as the game stands now, it'll dry up in a month once no one has anything left to do.
Again, this is just my opinion. Time will tell
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I completely agree, except for the time. I think it will take 3 months, before we see the great decline. That's the norm for new games. People play for a month, and see if they like it. If not, they go away. It's one of life's histories with MMOs, and while this is more of an RPG, the concept is still the same. Those that don't join in the first month, will wait for the second to avoid the queues. Those that don't in the second, will wait till the third, to see the game as a falling hero. With less and less hype, the game will get less and less new players.
The RMAH would be a draw for more players, but it's going to make a lot of people lose money, thinking they are going to make it. When gold hovers at $8-$10 per 1M, and someone tries to cash out, after a sale, only to find out that the fees are fricken HUGE, making them lose 1/2 of their investment, then people will begin to see. But I don't think the RMAH is going to make it's new deadline of May 29th. Blizz will let pass the bots, but the game hacks, account hacks, and dupe bugs, are going to hold it up some more.
As for PvP... there is PvP in most games, but not everyone is into PvP. Maybe 10% of the population likes PvP, so even with 3 million copies sold, after 6 months you can expect to have 300,000 players (usually lose 90% of the player base), and what, 30k PvPers? If PvP is the endgame, with no additional areas or group dungeons, then we can expect a rapid decline from there. The worst part about all this hype, is at least 50% of the population expects to make money on the AH... I am constantly asked to buy gold (own a site). But have few customers even though I supply other sites as well.