Both A330 and 340-300 share the same fuselage. The engine selection is likely to be the same.

Both Executive First and Economy class will feature the new seats with headrests... The audio-video system is the latest... For Y class, there is no PTV still but there will be bigger screens for movie viewing. For C class, it will have the latest seat with adjustable headrest and more electronic controls and adjustable personal lights. The audio-video system is bought from SONY. The system is called Passport and features the AVOD (audio-video on demand). Some A340s (Fleet no. 909 and 910) already got the new J class seats and AVOD system. The PTV screen is larger... I flew one of these new A340s in June, but the AVOD system is not installed back then yet. Fortunately, it is just YYZ-YVR and I slept all the way.