As a result, there could be made the argument that so much of bitcoin's current value is from speculators who may be holding out to see what happens after block 210,000, but then might unload large amounts.
Nobody knows, that's why it is called speculation.
This is a good point. I think the forum sentiment has been, at least so far, focused on the demand staying the same and the supply not increasing. But there could be a significant number of speculators who do not mine and have absolutely no intention of mining, that are waiting for the block reward to halve so that they can sell significant shares into the steady demand anticipating that the supply isn't going to be there.
I still think that, given what happened to Solidcoin, the initial result is going to be an increase in price, but I do think some people are expecting the price increase from November to December to be in the 100% range, to match the block reward halving, when it's probably more likely going to be increasing BEFORE that, and thus the change from November to December will be considerably smaller.
