I have been using Scribus to publish our in-house magazine as well as for
many other smaller uses. It has some very nice features over and above
Publisher, but also has a few little quirks that you will need to get used
to.

Stick with the version available on the repositories for now - there is a
new version out in Beta (Scribus Trunk) but it does have a few problems
that are not worth struggling with. (It is also not backwards compatible
with older versions of Scribus).