Having talked to them yesterday about this I believe its going to be later this month..
I am running 64bit WIN7 on two machines right now - Dell workstation laptop and a tiny little Lenovo S10 netbook - both are also running AV from another company with no issues so far - but I also would like to try out Blink...
Interesting part about this is I would hate to be in the AV position with WIN7 - becase if it slows down the "super fast new WIN7" I can only imagine the whining that will ensue...