[michael_nielsen]

On the issue of scores vs no-scores, it'd be possible to A/B test this, so half of HN users see scores, and half don't.

Metrics to track might include the number of comments made, number of hits on the site, number of upvotes / downvotes, and probably many more.

Some people obviously feel strongly about this issue, and it might be necessary to take steps to prevent gaming of the outcome. Keeping the metrics secret until after the test would help with this. So would publicly announcing that only a small (say 10%) but undisclosed subset of users will be used to determine the outcomes of the testing. So any individual user wouldn't know if their behaviour would affect the results, and so would have little incentive to waste their time trying to affect the outcome.

It'd be nice to take a data-driven approach to resolving this question.

[gnosis]

An interesting idea. But what would stop someone from continuously creating new accounts until they got an account which could see the scores?

[michael_nielsen]

You could exclude recently created or low-karma accounts, or at least track them separately. Indeed, there are many subgroups of HN users it might be interesting to track. E.g., new users, or users who've had accounts for a long time, or users with particularly high average comment scores, etc.