Do NoSQL datacenter aware features enable fast reads and writes when nodes are distributed across high-latency connections?
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We have a data system in which writes and reads can be made in a couple of geographic locations which have high network latency between them (crossing a few continents, but not [this slow][1]). We can live with 'last write wins' conflict resolution, especially since edits can't be meaningfully merged. 

I'd ideally like to use a distributed system that allows fast, local reads and writes, and copes with the replication and write propagation over the slow connection in the background. Do the datacenter-aware features in e.g. Voldemort or Cassandra deliver this? 

It's either this, or we roll our own, probably based on collecting writes using something like 
[rsync][2] and sorting out the conflict resolution ourselves. 


  [1]: http://stackoverflow.com/questions/2823295/networking-with-extremely-high-latency
  [2]: http://stackoverflow.com/questions/2087774/ways-to-synch-many-small-files-over-high-latency-network-connection