Given that I've found half a dozen of these deals recently it seems that they are pretty commonly offered. If you do buy enough iTunes stuff to warrant a $50 purchase then you should save yourself 20% and wait for one of these gift card sales. I'll pass them along on my Twitter feed when I see them.
p.s. have I mentioned my Twitter feed?
pps this article actually didn't start out as a way to plug my Twitter feed but it seems to have turned into one
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