There will be a new provider for AMD 64 platforms.  Broadcom recently bought Serverworks, who provided chipsets for Intel based servers, only.  Under Broadcom they will develop chipsets to handle the new AMD chips, thus continuing Broadcom's sordid history with Intel.

AMD said it will cooperate with Broadcom to develop chipsets for the Opteron processor. Broadcom entered the market for chipsets in 2001, when it bought ServerWorks, which specialized in Intel server chipsets. Product delays and newfound aggressiveness on the part of Intel have led to a recent decline in market share for ServerWorks.