(context post by Quantumplation)

The difficulty gets reevaluated and adjusted every 2016 blocks.

I created a realtime graph of the current block generation speed here;

http://titania.smutfairy.com/~rm/time.gif

MacRohard: Cool graph. It would be nice if it should time on the x axis and number of blocks on the y

Nice graph!  A moving average to smooth it out would be nice.

http://nullvoid.org/bitcoin/statistix.php says 212 blocks in the last 24 hours, or 8.8 per hour.