Oh, I just realized what you meant. Yes, I've often wanted an open-source app store of some sort where you had confidence you had found every user of a library. That would be the perfect place for CI if we could get it.
Perhaps you're also suggesting a package manager that is able to phone home and send back some sort of analytics about function calls and arguments they were called with? That's compelling as well, though there's the political question of whether people would be creeped out by it. I wonder if there's some way to give confidence by showing exactly what it's tracking, making all the data available to the world, etc. If we could convince users to enter such a bargain it would be a definite improvement.
I wasn't really considering that level of integration testing. It would certainly be cool to get detailed error reports from the CI tool. I don't see why you couldn't, since the code is published on the public package system, and you would be getting error listings anyway.
I don't think it would be creepy as long as it's not extracting runtime information from actual users. If it's just CI test results, it shouldn't matter.
Live user data would be a huge security risk. Your CI tests could send you passwords, etc., if they happen to pass through your code during an error case.