Well it seems that the D4 is the first camera to use this new card format.
And to help the format along, Sony have announced the first models of the new breed, and what's pleasantly surprising, is that they're very reasonably priced!!
While not exactly cheap, considering their eventual potential ... starting at this supposed 125Mb/s read/write speed ... they are comparable to some of the current fastest CF cards performance levels, with the added bonus that they're only going to improve(as cameras and the technology improves.
Engadget report that a 16G version of the Sony brand card will cost about US$129, which I reckon is quite good.
Good in that while it's a lot of money for a stupid little card, this is spanking brand new tech, which traditionally used to cost upward of $1K from the likes of ScamDisk and suchlike.
Extrapolate this current price, with the usual bout of discounting from retailers, and maturity of the technology .. We'll hopefully see hundred Gig cards at a few hundrd dollars, which basically gives SSD's a run for their money .. and we all know how stupidly expensive they are!
I paid $109 for my fast 16G CF card, which is a no name brand card from MSY .. and that was cheep!
So $129 for a 16G card, which is currently as fast as most CF cards, and probably faster in ultimate speed tests .. see DPR's overview of the D4 continuous shooting performance comparison between a CF card and an XQD card.
Sony have marked these cards as the H series, which obviously means that other series will become available, but I'm curious as to how much faster, better, more reliable and what file formats will become available with these cards.
.... see endgadget .... sony-xqd-memory-card
Oh! forgot .. I've been in the market for one more (at least 16G) card for my D300, and hopefully D800(next year), and it seems that Sony are to also produce both a USB3 card reader.... and an adapter, for what Endgaget describe as easy portability. I'm assuming that they mean an XQD to CF card adapter???
I hope so. I'll probably look into getting one.