Yes, it will be fine. You're not the first person to buy such a device early as a gift, you know. Also, who knows how long a unit has been sitting on the shelf or in a warehouse before purchase even when the buyer takes it home and opens it right away? They're obviously going to design the things to have some shelf life. As long as it's not powered on inside the box right now (and obviously it shouldn't be) it will be good to go as soon as it's opened, and probably won't even need to be plugged in right away.
And even if it does need a charge right out of he box, there's no harm in using it while it charges, so it's not like the recipient will have to wait to enjoy their gift.