The 451 research group has released a review of the skills professionals hold in the NoSQL realm. MongoDB has maintained a hold throughout 2012 with the highest rate of adoption, followed by Redis and Cassandra. The 451 team commented on their blog :
MongoDB’s growth means that it has cemented its place as the most popular NoSQL database, according to LinkedIn profile mentions. As the chart below illustrates, it now accounts for 45% of all mentions of NoSQL technologies in LinkedIn profiles, according to our sample, compared with 43% in September.