I love this. I think if it is kept as a limited inclusion (like once a year a contest-winner gets their card up on isotropic), it is just a splendid idea. Once we add a second or third however, I'll start to curl my nose a little. But having a traditional contest each year, where the winner is featured for one year (with last year's card being retired), is a superb way to do this.
I agree with the comment about rinkworks. He's not only a superb designer, he's a superb assessor of other people's cards. The discussion in variants is really useful to me, as a new player, as it generates more discussion about value, card assessment and tactics than just about any other thread I read.
Where the Variants forum can fail, is when new mechanics are introduced (like Hinterlands), because generally Variants are highly-derivative, so they work well to discuss the value of existing mechanics (by combining them, changing them or altering them to promote discussion and variants), but when a unique card like Traders comes along, you aren't as well-versed on the value of the card.
If you haven't yet already, read rink's sticky-post on the Variants forum. It is a guide to designing cards, it's an excellent read and highlights what makes a card great and what doesn't, and a noob, I found I learned a lot by reading it, not just about how to design a card, but how to assess and value all cards, even the real ones.
I think rinkworks deserves this honor. This isn't a seismic change in isotropic, it's a one-time award for a fan, who created a cool card and is pretty dedicated to the community here. Well done!