Looks like it is official now, where have a read of the first couple of paragraphs on this NowTV Sky Sports Pass Help Article.
I will reserve judgement until i have seen the Sky Sports VOD in action.
Was hoping for full replays, but the Help Article that i linked says "highlights" (hopefully the highlight coverage will be comprehensive).
Also i am hoping for 50fps VOD playback with a HD Boost Pass (otherwise it will be a big disappointment as far has i am concerned).
I hate 25fps playback with a vengeance when watching Sports 😠.
Read the first couple of paragraphs on the link page, where it states the supported devices from release of the Sky Sports VOD (where others will follow soon).
The NowTV Freeview Smart box should be fine with Sports VOD.