Re: Datastore HA files

google would have replied with the following:

http://www.yellow-bricks.com/2012/11/23/what-is-that-poweron-file-in-my-vsphere-ha-folder/

http://www.yellow-bricks.com/2012/04/30/with-vsphere-5-0-and-ha-can-i-share-datastores-across-clusters/

http://www.yellow-bricks.com/2011/07/26/ha-architecture-series-datastore-heartbeating-35/

Anyway, nothing to worry about. These are HA internals, way of keeping track of virtual machines and there protection state. HB files are used for "datastore heartbeating".