I must object. Hight supply is a problem if you want the price not to drop (which is implied by OP). A lot of miners decided to join when the price was at $30. They mostly joined for a quick buck, not because of bitcoin and it's features (see troll post above). These people have to throw their mined coins to the market, to recoup their investment and pay utility bills.
But people are continuing to mine, the network hasn't stopped running because a few decided to stop. Even after the cap is hit, transaction fees will get people to keep mining.
I didn't say anyone stopped mining. Mining is still profitable, even at an exchange rate of $5. I said many miners must sell their mined coins.
Just 3-4 months ago, one could mine 20 BTC per day with a 700 EUR machine. You need something like 20 GHash/s for that nowadays, that'll cost you $10.000, and if you look in this thread (watch out, hardware/cable porn):
http://forum.bitcoin.org/index.php?topic=7216.msg321184#msg321184, you can see that people are doing this.
I don't think they make such an investment with some "spare fiat money" they have laying around and then just keep the coins, they sell them.
Yes, miners sell coins. What is your point? How is this a mark against Bitcoins at all?