The card is rated at 133x speed, which translates to a data transfer bandwidth of about 20 MB/s.
What makes this card special is not just its price tag of about $700, but the fact that 128 GB capacity can be squeezed into a SD form factor. If you were to use the card to store 12 MP JPEG images, you would have enough room for 32,000 images - or about 17,000 21MP photos. Even if you store the data in uncompressed RAW format, there is space for 5200 uncompressed 21 MP RAW pictures.
The card can also be used for up to 36 hours of 1080p HD video or about 190 90 minute standard definition movies. Or you could install Windows 7 eight times.
The capacity and the price is well beyond of the needs of the average consumer, but it is no secret that these capacities (the card will also be available as a 64 GB version for about $500) will trickle down into the consumer space. Conceivably, they could serve as the only portable mass storage device you really need - storage that can be shared between your digital camera, video camera and a PC such as a netbook.