Updating OP with some more helpful links:
Friend Codes (GWJ google sheet)
Polygon online play guide
This also has links to their New Horizons Guide with a lot of helpful information for your first week or two of playing.
And of course the special edition Switch system comes out Mar 13, a week ahead of the game. But it seems pre-orders sold out in the US in about 4 days. Good luck if you want one. Nintendo did an official unboxing video last week.
Just saw this Polygon article Monday about paths, cliff stairs, and other fun stuff gleamed from screenshots.
And previews have already mentioned co-op play, which I am most excited about.
We'll find out more tomorrow!
Edit: official web site launched today.