As I understand it, the old setup (still live for the realms not yet upgraded):


  • Datacenter X
    • BG X1
      • Normal blades 1-10
      • Instance blades 1-10
    • BG X2
      • Normal blades 11-20
      • Instance blades 11-20
    • etc.

As it exists, BG X2 cannot use BG X1's blades as they're hard-coded to segregate themselves. Which is why you see some servers have issues and some not. Go look at the posts on who has these issues and they're almost always in the same BGs.

Once the "reconfiguration" is complete, it'll look like this:

  • Datacenter X
    • BG X1
      • Normal blades 1-10
      • Instance blades 1-20
    • BG X2
      • Normal blades 11-20
      • Instance blades 1-20
    • etc.

So what you'll have is a datacenter-wide pool/cloud/wtfever instead of arbitrary segregation. Might be region-wide pools but I kinda doubt that.