MONEY MONEY MONEY
If consumers are willing to shell out more money, then there's always the better alternative out there (didn't they already report about some less power-intensive alternative to the parallax barrier technology so that less power is needed to maintain the same brightness than using conventional PBs?
Next hardware revision, I'll bet, given that the price of such tech is cheaper, if not I don't think Ninty'll risk upping the price too much for a 3DSLite or whatnot again.