My upvotes/downvotes are worth 2 points each and my supervotes are worth 6. A person with between 10 and 100 karma on the forum has an upvote worth 1 and a supervote worth 2 (the scaling system is described in this code here I think)
My concern is that this system lends itself to groupthink, whereby the dominant views or topics are liable to get more karma, giving holders of those views more voting power, giving users that makes posts they agree with or that they see as relevant more karma, etc.
Dissenting opinions or posts not of interest to the in-group are liable to be downvoted (although karma is meant to reflect quality or relevance of a post or comment, this is of course misused), which both hides those comments but also puts off dissenting voices from commenting/posting in the future.
The justification for the current system is that people with more karma are more likely to be have better understanding and judgement, less likely to be sockpuppets or trolls and so are better positioned to vote. This is a system ported over from LessWrong (described here).
Concerns about the scaling system have been discussed on the forum previously, for example here.
Is this system more beneficial than harmful?
90%➔ 80% agreeOn group think: I think this worry can mostly be ignored if the elite-karma accounts have sufficiently diverse views. That being the case would mean that (a) diverse views aren't obviously being punished and (b) to voters with the most individual leverage are less likely to all vote in the same direction. If they top karma accounts were all aligned in how they vote or were even colluding to suppress comments / posts, then the downsides of group-think would be more pronounced.
I guess It feels like this should be a testable claim: do the most upvoted posts / comments conform to the views of the highest karma users? Given how diverse the viewpoints are of the +5000 karma plus users (even just the top twenty), I'm not even sure their is a single coherent view among the karma-elite.
Among the karma-elite are a few OpenPhil / CEA accounts, whilst the second highest upvoted account is Habryka (arguably OpenPhil's antichrist[1] and one of CEA's largest critique).
I haven't really thought about all the angles though and can imagine something like "the EA forum voting overly favours the bucket of people who have ~1000 karma and use the form everyday."
Probably the risk of group-think is more dependant on who the forum users are, rather than the specific mechanics of the forum.