Other technologies to watch:

1. GraphLab2. Unlike Pregel's Bulk Synchronous Parallel Model, GraphLab2 it allows non-synchronous updates, which is more efficient for approximate quantities. For instance, for AltaVista's web graph, most nodes only need to be updated couple of times, while some nodes need more than 60 updates.

2. Flume: it's an abstraction on top of MapReduce, you program as if your data is contained in Java-like containers, and it turns your program into series of regular MapReduces

3. ScalOps (http://cs.markusweimer.com/pub/2012-DataEng.pdf): that's a higher level abstraction prototyped in Yahoo Research, might get resurrected in Microsoft.

4. AllReduce