Top users

I believe top users of the day are those that have posted the most content/responded to the most discussions during that 24 hour period. Just as top users of all time are those that have the highest number of postings to discussions. I hope this helps. I made top user for the day once. It was tough though, I had to post over 140 responses that day.

On the number of quality discussions you are taking part in.Also on the number of meaningful discussions you have started and how good is the response.

People who post the most content and receive most responses. Content posted is comments posted, images uploaded (except images posted on your profile). Comments received is the responses all your discussions receive.