Just five months after it announced the production of the first Secure Digital memory cards in 4GB capacity at Class 4 speed -- capable of writing up to 4MB per second -- Toshiba is pushing the envelope even further today with the announcement of an 8GB flash memory card in exactly the same form factor.

The 4GB Class 4 rollout last summer may have precipitated a resumed freefall in prices for NAND flash components, just as retailers were starting to see the fallout from 2005 finally start to taper off. While 8GB SD cards are presently available, they're typically Class 2, which allows for 2MB/sec writes. Average prices for Class 2 4GB SD cards currently center around the $150 mark.

Doubling the speed of an SD card isn't just to reduce the number of thumb twitches during important saves. With digital video becoming a prevalent feature in still cameras, manufacturers are looking to be able to encode high-quality video at real-time speeds.

When the storage media is too slow, a still camera with video capability can't shoot footage for too long without having to pause to catch up with the saving process. A doubled speed could enable much longer video footage, especially with tricky codecs like any of the many flavors of MPEG-2.

The rapid doubling of capacity contributes a great deal to analyses such as last week's figures from iSuppli, showing that while NAND flash prices worldwide dropped in the third calendar quarter by an annual rate of 22%, shipments per megabyte grew by an astounding 44%. Toshiba is the world's #2 NAND supplier, with 27.8% of the market versus Samsung's 43.1%, though Toshiba's revenue from NAND flash grew last quarter at an annual rate of 25.6%, to $849 million.

Toshiba said today that consumers should start to see 8GB Class 4 cards in stores by January.