They've done this before. It means that the (perpetual) license is free until Jan 1, after which they start charging for new licenses. So get it now.
IMHO this is not kool.
Just a digital version of the old 'bait and switch'.
If it is [free for a limited time], please state that.
Fingerwag/fistshake/blackmark for NI in my book.
Curteye, I think you're misinterpreting the [free for a limited time] concept of this gift... If person A gets it now it's free and it remains free for person A. If person B gets it after 12/31 person B will have to pay 49$. It's not like person A gets it now for free and the same person A suddenly will have to pay a license after 12/31 to continue to use it.
So in my eyes there's nothing wrong with it (although person B will not be amused when person A tells him what a fool he has been :-) ), you can safely unfingerwag/unfistshake/unblackmark NI for this :-)