I upgraded the "Top Posters" addin from 1.2 to 1.5... it is under Quick Links and "Top Posters of the Month"

http://www.mapforums.com/misc.php?do=cybtpimx

You can now see the top posters for an entire year if you go to Month | All. (this was actually added in v1.3)

Versions:
v1.0 - Dec 09. 2006.
-Initial release
v1.1 - Mar 07. 2007.
-Text fields changed to menus
-Guests automatically excluded from stats
-Updated query for better compatibility with different servers
-Updated ACP settings to allow you to list available years and number of results in menus
v1.2 - May 01. 2007.
-Bug fix (post count in current month bigger than total post count for some users)
-Improved compatibility with right-to-left styles
-Some code optimizations
v1.3 - Aug 05. 2007.
-Added page navigation
-Added option to view top posters in whole year
-Added option to exclude users from stats
-Added option to exclude forums from counts
-Group membership checking works now for supplementary usergroups too
v1.4 - Aug 06. 2007.
-Fixed bug where guest posts are counted and shown as blank line in stats
-Page navigation also shown at the bottom of the page
v1.5 - Sep 15. 2007.
-Another "unknown poster" bug fix
-Fixed bug where month is switched to current one on page select
-Easier to set years (set starting year only, others are generated automatically)
-Several minor bug fixes...