So I have a bunch of domain controllers and a bunch of FSMO roles that I have to place. What do I do? Well, MS says to do the following based on their support article here which is summarized below:

General recommendations for FSMO placement
• Place the RID and PDC emulator roles on the same domain controller. It is also easier to keep track of FSMO roles if you cluster them on fewer machines.

If the load on the primary FSMO load justifies a move, place the RID and primary domain controller emulator roles on separate domain controllers in the same domain and active directory site that are direct replication partners of each other.
• As a general rule, the infrastructure master should be located on a nonglobal catalog server that has a direct connection object to some global catalog in the forest, preferably in the same Active Directory site. Because the global catalog server holds a partial replica of every object in the forest, the infrastructure master, if placed on a global catalog server, will never update anything, because it does not contain any references to objects that it does not hold. Two exceptions to the "do not place the infrastructure master on a global catalog server" rule are:
• Single domain forest:

In a forest that contains a single Active Directory domain, there are no phantoms, and so the infrastructure master has no work to do. The infrastructure master may be placed on any domain controller in the domain, regardless of whether that domain controller hosts the global catalog or not.
• Multidomain forest where every domain controller in a domain holds the global catalog:

If every domain controller in a domain that is part of a multidomain forest also hosts the global catalog, there are no phantoms or work for the infrastructure master to do. The infrastructure master may be put on any domain controller in that domain.
• At the forest level, the schema master and domain naming master roles should be placed on the same domain controller as they are rarely used and should be tightly controlled. Additionally, the domain naming master FSMO should also be a global catalog server. Certain operations that use the domain naming master, such as creating grand-child domains, will fail if this is not the case.

In a forest at the Forest Functional Level Windows Server 2003, you do not have to place the domain naming master on a global catalog.
Most importantly, confirm that all FSMO roles are available using one of the management consoles (such as Dsa.msc or Ntdsutil.exe).