What's the real issue?
Don't you think the real issue here is that Oracle, IBM and MSFT have formed an unholy alliance in the database realm and have artificially high prices for what should be a commodity? Most people aren't using the advanced features of a database, and the high-end stuff like Oracle RAC will kill you with server upgrades, application changes to make the app "RAC-aware" and more care and feeding than all the animals in a zoo.
The issue is that to protect Oracle's margins, and other vendor's margins, they keep the database prices high because NOBODY wants to swap out a database.
We've scaled back the work force so much, especially in IT, and so much is written about economies of scale and doing more with less, that IT people are frazzled to the nth degree, and Oracle and all the other vendors know they don't have to treat customers well in order to keep them around, because people have MBO's and other "must-do" tasks on their plates just to keep their heads above water.
The key here is that if EnterpriseDB truly has "Oracle compatibility" and has made it easy to replicate or even replace Oracle, then more and more people will dip their toe in the water and test it out. And if it works as advertised (which it appears it does) then they will do what FTD intends to do; use it on more and more applications down the road. And to do that, EnterpriseDB is going to have to earn the business and it sounds like their support and product is positioned to accomplish that task.
Oracle will pay attention when more big customers start to migrate away... Too bad it takes that before they begin to listen.