I've been thinking that Parse (and StackMob, Kinvey et al) need to provide a similar self-deployable solution at a reasonable price; this might be the motivation they need to do so.
This might cannibalise their business model in such an undeveloped market, they are all about lock in currently. There is definitely space in the market for an open source based MBaaS/BaaS that allows you to roll your own or use their hosted version.