For those of us in Australia, we usually have to wait for the USA and UK to get things first.
Seems this will not be the case for Loki and Falcon this time.
Disney's own website lists the availability of these characters as March 23rd, 2015
However, a few local retailers here in Australia are advertising an earlier availability of March 9th, 2015
Now it could just be a Marketing ploy - however I've usually found these dates pretty accurate from these retailers.
What I really want to know though is how to get my hands on the 2 new Power Discs. So far, JV has been relatively tight-lipped about it - but it would seem there's an announcement pending based on his recent tweets.
Interesting times!