1) All these white boxes are a custom MIDI system made by YES Audio under the orders of Vangelis and especially for his playing needs. The big terminal white boxes write on the back side "YES AUDIO, CUSTOM DESIGN FOR VANGELIS". This custom setup is connected to various synths, mainly racks. Also he uses 17 foot pedals, 16 volume and one sustain pedal as you see in the video. All this system help him to play live without the need of overdubs and sequencers. In fact, Vangelis compose/arrange/play and record at the same time! Its a unique technique and he is using it at least the last 25 years, this MIDI system is already in use since early/middle 90s.
2) Its obvious that this guy is genius. :-) I can't think any other keyboardist in any genre that he can play like Vangelis. What Vangelis can arrange, play and record in 5 minutes, the rest of keyboardists need few hours or more to do the same thing with all these DAWs and record methods they use. What Vangelis plays the most of the times, the result is a ready to release music work without the need of overdubs or post production. The whole system is connected to few RADAR hard recording systems, whatever he plays is always recorded. He uses Mackie consoles to connect his synths from his main setup and in his studio the main final console is a Euphonix System 5-B. You can see it in the video infront him.