This paper has received a lot of attention, so I won't talk about it much. I just wanted to point out that many of the people involved in this paper have been involved in distributed file systems for a while. Sanjay Ghemawat was involved in the Harp file system. Howard Gobioff and Fay Chang were involved in the Network-Attached Secure Disk research project at CMU, which, to my non-expert knowledge, is the first project that proposed separating metadata from data in distributed file systems, which is the core design behind GFS.
S. Ghemawat, H. Gobioff, and S.-T. Leung. The Google File System. In Proceedings of the 19th ACM Symposium on Operating Systems Principles (SOSP 2003), Lake George, NY, USA, October 2003.