I found Fuz and Alfio answers most helpful.
The two terms (sysop and admin) are used
interchangeably in the
Wikipedia user space. They both mean someone who as gone through
[[Wikipedia:Requests_for_adminship]] successfully, and can delete and
protect pages, and block IPs/names.
I found that "admin" is easier to understand,
since it's related to
similar non-wikipedia terms. Ironically "sysop" is a more accurate
description of the job, which is often limited to maintenance: the term
"administrator" suggets some power over the other users, while in
reality a sysop is just providing services to the others, and accepting
responsability for what he/she does.
I think that whatever the name used to described the admin role (ie,
admin, sysop or moderator), we should insist that wikipedia is open to
anyone. I think that no editor, whatever his status, have more rights
* in term of editing rights (eg, right to decide whether an article is
accurate, or neutral)
* in term of meta participation (eg, right to decide which categories
should be created, or to decide how the main page should look)
* in term of community building (eg, to decide rules for banning)
I believe there should be equality between sysops and non sysops, on all
projects. Sysops should only be at the service of the other editors. Not
decide for others, but apply decisions taken by all editors.
It does not matter which name we use. The sysops should not have power
over other users other than applying decisions made by all users.