I dunno.....trailers from FFXIII went straight from CGI to cutscene to battle and I could barely tell the difference
The differense is much easier to notice in the latest trailer though. This one was more like a target-render than actual ingame.
Last and current gens it has become possible to make simple cutscenes ingame instead of CG. But there are a lot of things that are absolutely impossible to make using ingame. The sequences with these flying ships for example: ingame like this will only be possible with PS6 if we are lucky.