I can only refer to hpHosts once again. Those sites you see listed 24/7 are not false positives at all. Some of them will have executables not detected by AVs. You see the idea? These sites are being flagged as RED in WOT. You must understand how WOT works - Im not praising social chitchat which becomes spamming/arguing in 10 seconds. Im not sure you understand the value Im happy with - and if you do it is flawed because 1. WOT dont work as system and 2. Avast is enough? Test, test...
Try orbasoft.com also a harmless site, clean according to Mcafee/Norton, with a harmless download no AV detects if you ask Virustotal. Oh yeah. This is actually harmless to install and is part of the gray area where Malwarebytes and others kick - also due to limitations of the old AV companies. But I dont mind giving that link. 2 weeks or so ago they had a registry checker thingy, now security. Same scam and there are tons of them - why WOT has a purpose.
Also you must understand that people posting on forums like this probably dont even need WOT at all. This is a little helper for less tech knowledgeable people. If set up right it does not require user action but you are correct in that false positives/gaming their system will render it useless. Ive been worried about that since I learned about WOT but it does seem to do the job when it comes to the not up for debate sites. I could not care less of a green lamp but bordering on yellow if child is 11.5 years old and live in Hungary - lets discuss...
If tiny malwaredomains is "quite good" how can hpHosts be questionable? I know those sources, they are also talked about on WOT forums - they ask for new ones even. Their strength is other companies are lazy. This is a 24/7 business, not weekly updates of half-dead links - throw hpHosts in your Google Reader and see for yourself. Use a linkify add-on in Firefox and do 10 fast ones, then 10 more. Cant spot anyting? I dont understand. Ive yet to see any healthy sites at hpHosts. Vast majority is so very obviously not for public consumption, just domain name give them away but you can land on sites in more than one way. Tinyurl type of linking is common. Phishing is also not always easy to "spot" but still not recommended. I really doubt you have visited many of these RED sites and wondered why the fuss?
So I simply dont believe you can test over a period of time or just randomly with many AV products and then declare WOT not to be trusted or not needed since X is already installed. Avast is good but certainly not 100% good. And neither is Avira with heuristics racing at full speed I should add... We are back to old hosts-blocking and Avast name is not to be found - but it still work! Actually I believe hpHosts is available as a hosts-file, also useful - paranoid but depends on definitions and also tools to fix that paranoia, hosts manager for example. If you believe WOT is wrong with RED flagging then plugin makes it easy to manage. I might not agree myspace.com is to be blacklisted, just one example there are more. Complicated since many users now dont mind added toolbars/extras and such with long EULA. hpHost is old school and does. WOT does not use anything from hpHosts btw. They have a black or white approach to sites, WOT grade sites not just blocking based on false info.
If you want to see half-baked blocking try OpenDNS. Check for forum for the many requests for malware-blocking. See how far they have come. Is not easy to make universal domain-blocking.