My biggest worry is Fukushima.
I hope the plants ok!
I also hope this isn't another foreshock. There was a 7.0 a day or so before the big 9 pointer back in 2011.
IIRC, the 7 was 50 hours before the 9, and is indeed a foreshock. There has been some chatter that this quake is NOT in the aftershock series, which can go on for years, but is it's own eq. Not been determined yet, though, so it could still be considered an aftershock of the 3/11 quake.
What is scientifically interesting and personally frightening, is that there HAS been an uptick in large EQs over the last few years, and, what I'm starting to see are quakes in places that I'm not used to seeing them...like today, in Texas. Or two days ago, in Colorado. There is a huge amount of energy which is being displaced from the west and the south, and I have my concerns that the New Madrid is starting to "wake" a bit.
I am also (as always) worried about the entire west coast - from Alaska down through northern Mexico...between the Cascadia subduction fault and the San Andreas fault (both of which are the east/northeast aspects of the "Ring of Fire") both are receiving a ton of pressure.
I just don't like all this energy moving around and changing locations like it is. It's just unnerving.
Best-
Herding Cats
ETA: The area I'm refering to around the New Madrid is called the North American Creton, and if you google a pix of it, you'll see how clearly some recent "oddly placed" quakes (like the Texas one, eg) are lining the edge of that area.