According to EBN, Intel is working with Taiwanese mainboard manufacturers, to facilitate the development of its Brookdale chipset to support Pentium 4 processor. Here is quote:

Asustek Computer Inc., Gigabyte Technology Co., Microstar International Corp. and several others have received samples of the Brookdale chipset from the CPU giant, according to Kelly Wu, country manager of the Taiwan branch of Intel Microelectronics Asia Ltd. The companies are in the process of testing the chipset on their motherboards, said a spokesman for Gigabyte.

Besides, Paul Otellini, senior vice president and general manager of the Intel Architecture group, told analysts earlier this week that Brookdale for Pentium 4 will transition to DDR SDRAM as soon as they would manage it.
The fact that Intel has already got the first Brookdale samples means that they would be able to launch it earlier than they had initially planned, if they got the desire to do it. For instance, we could see this chipset come out in Q2 instead of Q3. Everything is very likely to depend on RDRAM prices: if this memory remains as expensive as it is, then we have every chance to see Brookdale chipset much earlier.