Funny enough, the thing that had me thinking the most was the double ethernet ports. What would that be for? Two different networks? When one cuts out you just switch to the other one?
The current real Mac Pro actually has two ethernet ports too. There are a number of ways this could be useful.
Number one would obviously be to connect to two different networks. It could also be useful in a scenario where the machine is used as a server and you want a semi-redundant backup network line. It could also be used to directly connect to a NAS box via Ethernet.
you can bridge network cards to double your connection speed. You can connect to 2 different networks (load balancing or 2 different Internet Server Providers). You can run multiple virtual machines on your mac and separate traffic instead of putting all into one adapter. Multiple LAN is a norm now, especially if you in IT.
The dual ethernet in the current Mac Pro are only 1 GigE and gets around 100MB/s (real world)[0]. I aggregate the two cards to get better speed. Even a 10 GigE couldn't max out the SSDs in these machines which are 2GB+/s r/w.
[0] by real world I mean on a properly configured network. Many companies don't have that though so you often see "gigabit" speeds in the 30-50MB/s range.
1gbs is pretty slow nowadays and if you do any work that uses huge files that need to be copied to a NAS or a file server then moving up to 2gbs via bonding cuts transfer times in half.
10gbps is expensive, uses a lot of power, requires cat6, and rare outside of servers and SANs currently. Interestingly enough, there's a recent 5gbps spec that works with Cat5e that might be picked up by OEMs to replace 1gbps. Still no chips or cards out yet, so it will probably be a while. In the meantime, bonding two 1gbps interfaces gives you about a 200 megabyte/sec write & read speed off a SSD based server/NAS.
Should build in dual Solarflare or Mellanox 10GbE interfaces with SFP+ cages. Then you can use a TP transceiver if you want GbE, or DAC/fiber for 10Gbps.
