Intel's dual-core 8xx series along with their Celeron D line will be getting price cuts in this coming January, in-line with the release of their 65nm Processors. Celeron prices will drop from 5% to 13.6%, and the beefy Pentium D 8xx series will drop upwards of 20%. Currently, a Pentium D 830 retails for around $320 with the ATX packaging, and $350 for the BTX packaging. The 840 is considerably more, at over $540 at most retailers. The price cut planned for that particular chip is significant, bringing it down more than $100. Intel often reduces pricing on chips when a new line is introduced.
The new 65nm line will be dubbed the Pentium D9xx and the Pentium 4 6x1 (the latter being single-core). AMD is releasing 65nm processors as early as next month, but no details yet on what the CPUs will be. Hopefully Intel's cuts will encourage AMD to reduce pricing on the Athlon 64 line as well.