What they mean by a network install is that ALL possible files for the service pack are included in the package, whereas if it were for just one computer the updater would only download and install those files that needed to be changed...
for example I keep my computer up to date with all of the windows updates etc...I would therefore have a much smaller download...
someone else who didn't keep up with it would more than likely require the whole package...
I didn't bother with the automatic updates either, justb had my dad d/l it from where he works...
he said that he got the whole 277MB in just under 4 minutes...