User rights to update /var/www/

[James Pifer]

I have a new development server built to replace a Windows IIS server. I
have a few users who update the web server over ftp through some
developer application. On Windows I ran a small ftp server and they
would do their updates. On the new server I have vsftpd running. What is
the proper way to give them access to upload and overwrite files
to /var/www?

All the stuff (google and howtos) I'm finding on vsftpd is dealing with
users getting to their home directories rather than another place in the
file structure. 

Should I look at a different ftp server? wu-ftpd or proftpd? Still have
the file rights issue I think.

Other suggestions?

Thanks,
James