As any API out there, SE API does need some kind of analytics support. I suspect the SO team has plans for something like this, though I haven't seen anything hinted at yet.
Here are some of the data points I'd like to see:
- median number of unique IPs per day.
- total number of unique IPs for a specific time period.
- average number of API requests per day per unique IP for a specific time period.
- number of API requests for the top N unique IPs per day for a specific time period.
- % of unique IPs that hit the API limit (though ideally that one should be 0 :-))
As for data about individual IPs - that has some privacy implications and as an end user, I'd personally prefer if SO does not expose this information to the applications.
Edit: Upon rereading the question, I realized that indeed that's not what @George is asking about. (Even without his update. :-)) However, I'll leave my original answer below to collect dust and downvotes, so that others don't make same mistake like me and lose precious rep.
Short version - you can see that information in the response HTTP headers:
X-RateLimit-Current:298
X-RateLimit-Max:300
More info in the answer of Is there a way of querying how much of the API limit has been used?.
