I just logged into Pretendo not too long ago, and everything seems to be functional. Although, I'm encountering errors on the Friends list at the moment.
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if you're on wii u, i feel ya. happens a lot to me. here's the way i fix it (not sure if it works on 3DS): keep closing and re-opening Friends list until it works (up to 10 attempts, then i give up LOL) the most attempts i've ever had to do to get it working was 7 :/