I just got the flashing blue LED as I launched Streetpass Mii Plaza, and decided to run it's in-app updater on the offchance.
It downloaded and installed an update (100Mb or so based on download time), but I can't see anything changed.
No new puzzles, and the only bug I'm aware of (Streetpass Battle doesn't save rankings marked as 'seen' unless you save something else afterwards) hasn't been fixed.
Edit: My 3DS is an EU unit in the UK.
Changes found:
• Total piece count returns to Puzzle Swap
It downloaded and installed an update (100Mb or so based on download time)
Edit: My 3DS is an EU unit in the UK.
Changes found:
• Total piece count returns to Puzzle Swap