It would be nice if there was a way to assign Z39.50 servers to groups so you could search for similar titles in a batch. For example, it might be helpful to assign several servers to a Spanish group or a DVD group. Then when you are searching you could click on the server group name and the search would execute across all the servers in the group. It would provide efficiency and accuracy in cataloging.
Agreed this would be a great addition and especially helpful in a consortium setting where each library does their own cataloging. For example, we have some targets that use conventions very similar to ours for DVD records, but that target's book records end up needing more edits. So if we could place that target in a "Good Audiovisual Records" group and leave them out of the "Good Book Records" group, then we could avoid some of the extra work needed to fix bad book records that are pulled in from the good AV target. For the interface/usability design, it might be nice to borrow from the user permissions page, where the groups are top-level checkboxes and the individual targets are collapsed inside, but you could still expand the groups to check and uncheck individual targets within a group if you wanted.