Memory chips keep getting denser and denser, so it follows that memory makers would get sick of fashioning kits out of the same old 2GB modules. Sure enough, OCZ has introduced a new 4GB DDR3 module, which it's offering both as a standalone product and as part of an 8GB dual-channel kit.
The OCZ DDR3 PC3-10666 Gold Edition 4GB module and 8GB dual-channel kit are both rated for operation at 1,333MHz with timings of 9-9-9-20 and a voltage setting of 1.65V. OCZ claims to have designed these products for both AMD and Intel systems, although it also talks of optimization for Intel P55, H55, and H57 platforms. Perhaps that's a reference to the voltage rating—Intel recommends no more than 1.65V to avoid damaging the memory controllers in its Nehalem-based CPUs.
Otherwise, OCZ dresses the modules in a "Gold Layered Z3 XTC Heatspreader" and covers them with a lifetime warranty. The company has yet to announce pricing, but for what it's worth, existing OCZ Gold 4GB dual-channel kits start at $117 shipped. You can probably count on the firm charging more for even the lone 4GB module.