I think the anonymity is okay - anyone who has used ebay for some time will remember the negative feedback issues they suffered - the vendor and buyer got to have a 'showdown' in the feedback comments - they have now made this anonymous as a result.
I think posting names will only serve to cause arguments.
I think the system is good - it depends on how you use it - most support sites offer some kind of 'did you find this answer useful' type scoring - in this type of scenario is is good. But see more I guess it might not be suited to all sites / situations.
I would say that it would be better to be able to enable / disable it as necessary.
Regarding the trolls - one or two ratings is not really an arbiter of a good / bad post but 3/4/5 or more usually is.
I think posting names will only serve to cause arguments.
I think the system is good - it depends on how you use it - most support sites offer some kind of 'did you find this answer useful' type scoring - in this type of scenario is is good. But see more