We have a growing lineup of SystemReady ES certified hardware that will make good OSS upgrades. New platforms on our LX2162A based SOM will be especially good for this application.
The core count and network processing is the same, but the number of SERDES lanes is half. This allowed the SOC's die size to be much smaller. You can fit 4 SOMs in the space of a single CEX7 module.
Now that you mention that, it's quite an upgrade over my idea of putting 32 Octavo easy to interface packages (you need to connect like 5 balls for what I want) along with a ethernet switch and make a cluster of 32 puny nodes...
The number 32 is important because a stack of boards should look like a Thinking Machines CM-2a (http://www.corestore.org/cm2a.htm) and each CPU would control one LED (or three - Octavo now has a 3-core, two puny, one even punier, part, ending up with only 10 nodes per board).