DXD is not DSD (direct stream digital, one bit recording). DXD is a PCM format that is a very high sampling rate of 352.8kHz / 24bit. Merging Technologies and Pyramix incorporated the DXD format into their recording systems to provide PCM like tools at a much higher standard than was available at that time. DXD at 352.8 is approximately 4x larger file size than DSD2.8 though, among avid DSD recording engineers, some may hear a more PCM like quality to DXD that is not to their liking.
The Sonoma system for recording to DSD has limited editing capabilities but can stay in the DSD format without going to PCM/DXD. The limitation for the Sonoma system is that is currently only records in DSD 2.8 (also called DSD64)
Some labels, like 2L, have chosen to record in the DXD format and release in DSD. This allow for more editing that is common to PCM. DSD as a "container" for DXD is a very suitable solution for delivering files to end users/music lovers. Some labels, like Channel Classics, choose to record in DSD and on occasion will convert to DXD for minor editing purposes. Some labels, like Blue Coast, record using the Sonoma system and limit their editing to stay in the DSD format.
What the future holds is up to the consumer. Eventually, the acceptance of DSD will provide recording equipment capable of DSD tools equivalent to that in the PCM world. As a container, DSD has proven itself to be efficient for delivering files at about 25% of the file size of industry equivalent PCM formats. As broadband continues to have bigger 'pipes', DSD could be the optimum choice for streaming and downloading our music in the future.
The best test is to listen and decide for yourself about DSD vs DXD or PCM.