Not surprised, can't tell you how many parents I know would rather give their younger kids their cell phone or tablet to play games. Frankly it is surprising but I don't see it as really as devastating the handheld market as some analysts seem to say it is.
The 3DS is still building its market and devouring the previous DS market, time will eventually shift it but I do believe the mobile/tablet share is probably there to stay because it is easier especially if parents don't really care or think the kids can break the device or do something that screws them.