Newly leaked slides reveal that Intel's Z97 and the rest of the 9-series chipsets will not support SATA Express. Earlier this year the rumor mill claimed Intel's next-gen chipsets would support this technology but it appears the rollout has been delayed to a later point.
SATA Express is part of the Serial ATA 3.2 specification that was ratified in August. The spec introduces updated connectors that support both existing SATA gear and PCIe-based SATA Express devices. Those devices can have as many as two lanes of PCIe 3.0 connectivity, delivering 16Gbps of bandwidth—a big step up from 6Gbps SATA.
Along with a fatter pipe, SATA Express provides a choice of AHCI or NVM Express host interfaces. AHCI provides legacy compatibility, while NVMe is tuned specifically for high-performance SSDs.