I have several systems that use Vim, and on one I am unable to view/edit zipped files. I believe I have the right plugins because my other system with Vim 7.0 works correctly with the same plugins.
I get an error:
$ vi admin.war
~
...
~
***error*** (zip#Browse) unzip not available on your system
My machine:
$ uname -srmo
Linux 2.6.35.4-rscloud x86_64 GNU/Linux
$ vim --v
VIM - Vi IMproved 7.2 (2008 Aug 9, compiled Sep 28 2010 11:05:08)
$ find / -name "*zip*.vim"
/usr/share/vim/vim72/autoload/zip.vim
/usr/share/vim/vim72/autoload/gzip.vim
/usr/share/vim/vim72/plugin/zipPlugin.vim
/usr/share/vim/vim72/plugin/gzip.vim
All you need to do install unzip, and it will work.