Ed Steer's comment on the margin hikes:

It's perfectly normal for the CME to raise margin requirements as the gold price rises sharply. Well, that's not what they did. They raised them as prices fell sharply...and announced it after the close of trading yesterday. As Ted Butler has pointed out, they do this because it helps the Comex short holders at the expense of the longs. This is precisely what they did in silver in the days that followed the drive-by shooting on Sunday, May 1st.