Update: I had a chance to talk to the company this afternoon and garner some details. The CF card uses UDMA Mode 4 to attain its fastest speeds, which, as yet, no digital cameras support, and it will be a little while before we see any.
Been worrying what flash card will be able to keep up with your new Canon EOS-1D Mark III? ATP will be ready for you with a 300X (45MB/sec) ProMax II CF card in 2GB ($64.99), 4GB ($129.99), and 8GB ($249.99) capacities. Like its ProMax predecessors, the ProMax II is water, dust, shock, and extreme-temperature resistant.
The company also announced a $149.99 8GB Class 6 SDHC card.