Glaring omission in the "Tech Specs" section - my money is on somewhere between 16x16 and 80x80
16x16 is low enough that it would be obvious in their promo pics (unless they faked them and that's not a real product image).
64x64 or 80x80 with visible camera overlay seems quite plasiable
If you look at the pics taken from their CES demo unit, the thermal image looks very blurry, and 16x16 with some heavy processing could just be possible, though if you were designing a new sensor from scratch, as appears to be the case, then 16x16 would probably be too low to aim for. From the pics I don't think it's anything like as high as 80x80.
ULIS (I believe now owned by Flir) have recently released an 80x80 sensor.
I would guess the limiting factor is the lens, and the resolution may well be decided to match what a cheap lens is capable of.
The act that they have not said what the resolution is speaks volumes - it is clearly low enough that the figure would discourage people from taking it seriously.
This is the only real video I can find - looks like 9fps
Also a surprising amount of lag - watch when he waves his hand in front of it