Atomic batches in Cassandra 1.2
datastax.com
datastax.com
That's a pretty concise way of expressing why we started building our product here at FoundationDB (http://foundationdb.com/). We're building a distributed key-value store with ACID transactions precisely so that developers building cool projects can stop worrying about all of the ins and outs of maintaining consistency by hand. If you'd like to give it a try, please feel free to sign up for our alpha -- it's just a quick form on our website (http://foundationdb.com/#get) and then you're welcome to download the software and check it out.