Mixpanel (YC S09) launches "Analytics for your customers."
techcrunch.com
techcrunch.com
If so, that's a pretty good idea.
Plus, presumably some of the small companies already using Mixpanel will be big-company-worrying medium companies in due course.
On a related note, what has attracted us to Mixpanel so far is that is is very generic - I've not come across a case yet that can't be made to work with the event triggers. Mind you, I've not used it live - just read the docs - so I may be speaking out of my cloaca ;)
Big players move slowly. Most of the times it is easier, faster, and more profitable to buy the startup instead of building their own product to "compete".
E.g., Google could have built something similar to adMob, yet it decided to buy it.
If Mixpanel's product becomes sufficiently powerful and flexible, it can become the standard for "analytics on someone else's site" just as much as Google Analytics is the standard for "analytics on your own site".