Proper sleep for the MacBook Pro
Ever wondered why suspending on your new shiny MacBook Pro is taking so much longer and seems a bit more flaky than on your old Powerbook? Have a look what hibernation mode you are running in:
pmset -g | grep hibernatemode
Obviously Apple changed the default hibernation mode from 0 to 3 which also writes the content of the memory to disk.
sudo pmset -a hibernatemode 0
If you change from 3 (or 7) back to 0 you are back in wonderland. You can then also free some disk space and remove the image. If you switch back it will be re-created.
sudo rm /var/vm/sleepimage
For more in-depth information see this article.