Capture One version 7.1.3 has added an interesting feature (which is currently labeled beta): you can import a Lightroom catalog into a Capture One catalog in just two clicks (and a few hours of waiting for the import/preview-generation).
We have extensive details here:
Capture One's New Lightroom Catalog Import Tool Of note exposure, contrast, saturation, crop, orientation, rating, color tag, and copyright are all imported.
It seems a very clear shot across the bow of Lightroom geared towards users who would like to use C1 for it's raw processing quality and pro features (overlay, color editor, focus mask, tethering with live view etc) but are locked into using LR because they have an extensive catalog.
I'd say the feature works pretty well as-is, but it is very clearly marked as a beta, so we recommend strongly against using it on any production machines, and only on copies of your catalog (not the master copies).