Last modified: 2011-03-13 18:06:25 UTC
At the top of the User Contributions page, it should specify how many
contributions have been made. "You have made 287 contributions using this
account since 21 Aug, 2005"
Traditionally there's been resistence to enshrining edit counts. See eg:
There are various extensions in CVS which can do this, however. In fact, there's
one which does exactly what you ask for; see the "contributionseditcount" extension.