Another key fact is that "big data" is actually not that common, especially when it gets to the analysis stage.

The median job size at Microsoft and Yahoo is only 15GB. And 90% of Hadoop jobs at Facebook are under 100GB. Clearly you want to be able to crunch large log files, but in terms of day-to-day analysis the files are much smaller than that. (cite: http://research.microsoft.com/pubs/163083/hotcbp12%20final.p...).

At Sense (http://www.senseplatform.com) most of the clients we work with are struggling not with the size of their data but with tricky modeling problems that don't fit into standard black boxes and with integrating analytics into actual production systems. Adopting something like Hadoop for these tasks is not very productive.