That is, with 2 sockets, same amount of RAM and PCI-E slots?
That looks like a decent option for most graphics pros and can be later on upgraded to dual CPUs if need be.
Once again, what Apple is asking for the memory upgrade is quite steep.
I wonder if the machines can accept standard 800Mhz FB-DIMMs (say from Kingston ValueRam line). These are much cheaper than Apple BTO options.
BTW, even with 1600Mhz bus, and two separate dual channel memory pathways, 2 x quad core is still memory starved in some highly RAM bound operations. That won't be fixed until merom and it's new platform arrives (maybe this year on paper, but it won't be until Q1/2009 earliest before it ships through Apple).