A (much) longer version of our Cassandra status inside Facebook, Twitter, Digg and Friday’s updates on Cassandra usage at Twitter on HighScalability.com:
Twitter may not want to make the same mistake. Does this mean Cassandra and NoSQL suck? No, I think it’s just smart project planning. It’s actually OK to have multiple platforms for different purposes.
That’s just a different way of saying to use the right tool for the job, the motto that I’m trying to associate with the NoSQL ecosystem.