Would you wear this in the daytime...

You could definitely wear it during the day! Pair with dark grey opaque tights, nice flats, and a great jacket and you're set! Just make sure you wear casual jewlery with it, that will definitely make a big difference. (like the necklace the model is wearing!
 
Yes, especially if you dress it down like with flats or with a semi-"frumpy" cardigan over it, or a turtleneck underneath.

I agree, this dress can definitely look great during the day time, provided you stay away from accessories or jewellery that is too sparkly and go for simple block coloured shoes (preferrably closed rather than strappy sandals) and a simple cardigan or jacket.