If you are shooting weddings and your workflow involves importing photos from multiple cards simultaneously, you may want to hold with the latest Lightroom CC update.
I know of quite a few wedding photographers that use a USB hub and several card readers to unload all their cards simultaneously into lightroom. While this process is not faster than unloading each card separately, it takes away the need to babysit the process.
The latest lightroom update released yesterday take this ability away with a new import screen. The import screen forces you to select one source for import, either a single drive, a single card or your photostream (or a folder).