Thanks for sharing the cool pics phat! I don't know if you've already seen these but here's a link to some good pics that a guy, Dave Landreth, took of the Shoshone lake and Heart lake area with a pic of a grizzly that he had to use some pepper spray on.
http://www.griztrax.net/hiking/Yellowstone/ShoshoneLake/ShoshoneBP.html
He also watched a battle between 2 bull elk over a harem right from his campsite.
At Heart Lake there are big scratch marks on the food pole he was using!
The thought of seeing a bear on our hike is both scary and exciting. I just want to make sure I can keep my cool enough to respond the right way in different situations.