If people didn't want services on free services, then the people who were using them to make money would be up the creek. Adding 'customer' in front of that concept doesn't change the underlying relationship.
Human customer service doesn't scale well. The number of false flags Twitter will get on this report button is non trivial. Most people are assholes when they get power, and that report button is power. It will be used by some to remove people they don't like from Twitter. We've seen the same on other services (youtube), and we'll see it here.
We have computers that block spam, remove content from Google's index, drive cars and win at Jeopardy. They could certainly remove a lot of abuse, and that would be worth doing.
I'm not convinced it would result in wrongly removing a lot of people, since there is some form of karma in the number of followers and the number of lists someone is on.
Of course, it would be nice to have some recourse to an independent appeal if something goes wrong. However, Google manages without one (1), and its decisions can have devastating personal and financial consequences. That's not the case with Twitter, where there is no real barrier to creating accounts. Including spam accounts.
(1) Unless you happen to be buddies with someone at Google.
Mmm, well, there you're changing your argument on me ^_^;
Okay, let's talk about that instead. Problems: False positives, (from whose perspective?) low staff to customer ratio.
Potential solutions:
Recruit volunteer staff
Pros: More staff.
Cons: Some of them are going to be evil.
Let users report people they don't want to hear from (as you point out, this is how it will work)
Pros: Reduces staff tasks
Cons: Again, might be used for evil
So, essentially what we seem to be looking at with the above problems is a trust issue. If you give people binary access to total power, even on a probabilistic basis as per the report function, then it's going to be abuse.
Potential solutions:
Give people more limited forms of power than banning and not banning.
Pros: - varies
Cons: Less deterrents?
How might we do that?
Potential solutions: Let people ban others from their accounts.
Pros: No longer have to worry about people who just don't like someone banning them.
Cons: Loses a lot of the social deterrent effect, people who joke about rape probably don't care about continuing to talk to the person they're attacking anyway.
Cons: Doesn't let you network with people who are likely to share your values, so you'll get exposed to attacks anyway.
(This seems to be the current state of affairs - I don't really use twitter so I don't know, but suggestions on pages seem to imply it.)
If we solve the second problem there, the first one becomes less of an issue. At this point it starts to look like a networking and evidence problem. If we have ban groups - that you can join or unjoin as you please, to make abuse less likely, and have each individual user's decisions absolutely override any group level decision for their account.
Okay, what are the potential problems with that?
How would you vote?
If someone's banned from one person's account gets banned from all of them, then as the group increases the power of any individual within that group will increase.
Require more than one person to make a decision to get rid of someone?
How do we stop groups of thugs just voting to shut someone up?
Choose a representative sample? Say by forwarding the reported post to three people within the group and having them all sign off on it.
Downside is you duplicate work - upside is you reduce the potential for them all to be evil - and if the group itself is evil then it's not a group that people would want to be part of anyway.
How do you keep trolls out? If the group consistently votes against your reports, then your reports stop being received?
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I don't know, admittedly this isn't my area and this is like ten minutes thought. But it doesn't seem to me like an absolutely unsolvable problem as much as it seems a bit tricky.
The situation for Twitter is messy no matter what they do. A report link also opens them up to a tiny liability of 'I reported it and you did nothing', so they'll likely default to leaning on ban first ask questions later. Again, just like Youtube has. Messy, but interesting to follow what they do.