This morning it was all "Where's Waldo?" on my computer as I hunted and hunted for the new app store after spending far too much time updating my system. It turns out that I don't need to upgrade my glasses, just my recognition skills. The new App Store icon is automatically installed into your Dock under 10.6.6, just to the right or below the OS X finder icon, into the second slot on your Dock.
App Store is an application, just like most of the other items in the top or left portion of your Finder Dock. Removing it from the Dock adds a little room back into your applications collection -- and you can do this without losing access to it from Finder. The secret is that App Store is built right into the Apple menu at the top-left of your finder window. Why take up precious Dock space when you can get to the app so easily?
If you're looking to conserve space in your Dock (and, frankly, what Dock-aholic isn't), you can easily remove it and still find it when needed. To remove App Store, just drag it out from the dock into the finder. You'll be rewarded by a lovely visual poof and an accompanying sound effect.
Of course, if you change your mind and decide that you want App Store back in your dock, just hop into your Applications folder and drag the icon from the folder window right back over into the dock.