[Development] Clarification needed for Qt Script's future over QJSEngine/Value

[N. N.]

I was looking at using QtScript for a project and noticed that all work has been "ABANDONED" for using the new java script engine V8 as noted in http://qt-project.org/wiki/V8_Port and

then pouring over other bug reports & the mailing list about QtScript and how QtScript won't be updated to use a newer JavaScriptCore since it would be too much work to maintain.

The talk is that for Qt5 there is QJSEngine/Value API instead, but, that is a smaller subset of features over what QtScript offers now.

Reading about QJSEngine/Value there seems to be no official API way for exposing a C type callback, so everything has to go through QObject bindings instead, correct? 

Does this mean that QtScript will eventually be deprecated in favor of QJSEngine/Value since 
QtScript will not be updated any longer with any improvements and basically be left in a "as is" state with possible bug fixes?