You can import OPML! When you login, just click on the green + button in the bottom-left. (There's a callout that says, "First things first..." right above it). There you can easily import OPML.
Yes, I know it should look for duplicates, with an option to erase. Unfortunately, this was too low on the priority list. But it's sitting there, waiting to be implemented sometime in the next few months.
