Intel has placed their money on the proprietary memory design developed by Rambus, Inc. On the surface, this looks to be a very fast solution for system memory due to its fast operation (up to 800 MHz). The reality is, however, that the design is only up to twice as fast as current SDRAM operation due to the smaller bus width (16 bits vs. 64 bits).
Despite the claims from Intel and Rambus, Inc., there are some potentially serious issues which need to be addressed with this technology. The higher speeds require short wire lengths and additional shielding to prevent problems with EMI. In addition, latency times are actually worse than currently available fast SDRAM. Since most of today's applications do not actually utilize the full bandwidth of the memory bus even today, simply increasing the bandwidth while ignoring latency issues will likely not provide any real performance improvements. In addition, processors operating with 800 MHz bus speeds will certainly require more than double the current memory bandwidth.
While these issues are serious enough, the biggest drawback to the technology is that it is proprietary technology. Manufacturers wishing to implement a solution with DRDRAM will be required to pay a royalty to Intel and Rambus, Inc., and will also have no real control over the technology. This is not an attractive outlook for most memory manufacturers who have no desire to essentially become chip foundries.