It's easy to understand the draw of the DCTs: better performance and greater efficiency. But there are also problems. For instance, two clutch mechanisms mean (theoretically, of course) twice the potential cost of repair, and DCTs generally cost more than either standard manual transmissions or conventional automatics with torque converters.
Xtrac, a company firmly entrenched in transmissions for racing applications, has developed a new technology called Instantaneous Gearchange System that uses a ratcheting mechanism to couple the gear hubs with the main shaft. The system has been under development for two years and has reportedly seen racing duty by multiple motorsports teams.
Apparently, the IGS technology will be less expensive than other dual-clutch transmissions and could potentially be adopted by various global automakers. Hat tip to David!