nmillar: No idea; they agreed to refund me for their error a couple of days ago, but I've just tried to log in to find my account has been suspended.
GameRager: They OVERCHARGED you, apologized, then suspended you? Wtf? 0.0
It's actually a bit more complicated than that. A gift purchase failed at Steam's end (Civilization V to be exact) despite the PayPal funds going through. Steam Support advised that the money was being held by PayPal and should be returned to my account in three working days and to try my purchase again. Obviously, by this point, Civilization V was no longer available at the sale price, so I bought a copy from D2D to gift instead.
A week later, still no returned money, so I raised a dispute through PayPal and a few days later the original gift purchase went through. Since the D2D gift purchase had already been redeemed, this extra copy was now useless. Having contacted Steam Support again, they agreed to refund the money to my PayPal account.
Two days later and my account has now been suspended.