I had an inkling that this might come to be. Compellent makes filer heads that connect to storage arrays on the back end. Units are thin provisioned with lots of tiering and migration bits built in.
Compellent isn’t an HPC play. Really they are more an enterprise-y type of play.
I do know a few Compellent people (hi Russ!), and the products will fill a hole in the Dell line. However, there are still other holes to fill, so I expect Dell to continue down its M&A path.