Reading Simterical's comments, I asked myself, what are the advantages and disadvantages of having Edit Counter as an extension, and not a Toolserver project?
Being part of MediaWiki's (extensions) code allows faster internationlization of messages. Also, there will be no replication lag to take into account. On the other hand, *perhaps* it may make creation of graphs a little harder, but I'm not sure (since I regularly create several graphs using PHP and GD with my Toolserver account).
What do you think?