Get the Top Authors based on entry counts? I want to be able to display Top Authors based on their entry counts. Has anyone ever tried doing this?
Here's how I did something similar, now edited the code for you to work with users. The better approach would be to do this with a plugin, because, as you can imagine, the only way doing this with Twig will end up in lots of DB queries, so please make sure to use the cache tag with this: 

{# Build an associative array of user IDs to the count of related entries #}
{% set userData = [] %}

{# Go through all users #}
{% for user in craft.users %}

    {# Get total number of entries this user is the author of #}
    {% set count = craft.entries.authorId(user.id).total() %}

    {# Save entries count and ALL user data we gonna use to our array #}
    {% set userData = userData|merge([{ entriesCount: count, userId: user.id, userName: user.name }]) %}

{% endfor %}

{# Sort, reverse-sort and pick top 10 elements of the array #}
{% set userData = userData|sort|reverse|slice(0, 10) %}

{# Print the top 10 list #}
{% for element in userData %}
    &lt;li&gt;{{ element.userName }} ({{ element.entriesCount }} entries)&lt;/li&gt;
{% endfor %}