The NVM Express driver has been around for the better part of the year now since the specification was announced, but it looks now like it's finally ready to enter the mainline Linux 3.3 kernel.
The NVM Express specification was released in March of 2011 by the NVMHCI Workgroup of which Intel is a leading member. The NVM Express Linux driver is largely the work of Intel's Matthew Wilcox.
NVM Express, short for the Non-Volatile Memory Host Controller Interface Specification, is a specification for solid-state drives (SSDs) over the PCI Express bus. This is an attempt to standardize the interface for SSDs wishing to use the PCI-E bus. While Intel's contributing this driver, any hardware that complies with the NVM Express 1.0 specfication should be able to take advantage of this open-source support.
Since its debut last year, the NVM Express Linux driver has undergone several revisions and weighs in at just under 2,000 lines of code. Among the other companies involved with NVM Express include Dell, SandForce, Oracle, Micron, Samsung, and OCZ Technology, among many others.
The pull request for adding the NVM Express driver into the mainline Linux tree can be found on LKML.org.