Custom Press would be even more useful for me if it came with (or worked beside) a Search interface. More than just searching custom fields, it'd be incredibly useful to define those fields in the backend, then have a generated-on-the-fly series of dropdowns that'd let users define their search by custom categories.
To make this less abstract:
I'm working on a local business reviews site. We have tons of meta-info in the custom fields, such as location, price, late hours, etc., and it'd be great to allow users to refine by those parameters, and generate a search results page.
This appeal to anyone else?