Currently when speaking of "IE" one needs to specify which one i.e. 6, 7,
8... as each one is a different animal. The new 8 comes closest to meeting
web design standards but most professional designers would be quick to point
out that it still lags behind Firefox, Safari, and Opera. Microsoft gets away
with a lot because of IE's dominance (it is my default browser (v.8) but I
use the other 3 for testing).
The correct way for centering is
margin-left:auto;
margin-right:auto;
but only IE 8 supports the correct way. Previous versions require the
incorrect -
text-align:center;
Publisher is designed to generate html code for the IE browsers (pre v.8) so
a lot of its html can render oddly in the other browsers. Due to IE's
dominance most people assume incorrectly that IE is doing it right and
everyone else is wrong. Only IE 8 gets it right, and ironically enough IE 8
comes with a compatibilty button that allows you to view incorrect html coded
for IE 7 - properly. Proper for IE 7 - that is.
If supporting the other browsers is important to you then you want to
install all of them and test your site across all of them. To support
centering correctly typically involves adding custom code with the html
fragment option.
If you want to learn more about these things and more I recommend
http://www.netmag.co.uk/