I tried to add multiple people and they try adding me in SSBB. ALright, so we put the friend codes in and the correct names , but it still says Awaiting Registration. This has happend for 2 people. There are other people who are added , but it seems that some won't.

I think you have to wait a while like the Wii registration...

 Well one of these people was added yesterday while some others were added today and registered. 

Try re-adding them....

I noticed the ones that seem to register immediately are the ones that are online at the same time as I am. Me and my brother exchanged FC's over the phone and we showed up on each other's list pronto.

^ Good point.

The servers are down currently and Nintendo is trying to fix them. I heard it will take a week from launch day.