I like that we can track our visitors, their behavior/interests etc., which is very helpful in understanding what they are looking at when browsing my site or clicking through to other pages of mine (which helps me understand where more content should be placed).
The only thing about this tool as far as tracking goes would have been if it had some sorta way you could see how many people were actually using your page vs just being there but not interacting with anything - so i guess thats something else! It's really great because its helping us better target future customers by showing them exactly whats engaging users right now- especially since most things online these days seem kinda "samey".