This conversation has been merged. Please reference the main conversation: Lightroom: LR4.1 Slow Import of RAW files
The bottleneck is not the card reader - it is a USB 3 unit that reads at ~62MB/sec, so to just transfer the files takes only ~1.5min.
Whilst importing I am doing nothing else with Lightroom (or the PC), yet the Lightroom process is using ~96% of the processor and 1.5GB of RAM.
It is slow with other imports, but nothing like this.