Vis.js demo - (Yet another) Javascript visualization library. I love the relative graph approach, I find it easier for Python developers that d3.js (which I also like) -
Predition.io - a machine learning server for developers and data scientists. Built on Apache Spark, HBase and Spray. Haven't used it but it seems very interesting -
Django performance - 4 litlle tricks - I'm familiar and experienced with Django but not deep dive. Possibly those are very basic tricks but for me they were good to keep in mind
Deep dive into elasticsearch storage - as I currently work a lot with elasticsearch (should say elastic..) I find this post very interesting
Amazon machine learning - the new buzz in the neighborhood