Of course these definitions and comments will be severely doubted by somebody at this board, but I, yes I (that is: the only source of athority of this is me), think that:

"Der Verfall"/"E Nominee", "Beam & Yanou" is german pop-techno = euro-house, which also include "Sash" and "Brooklyn Bounce". At least, this was the name for it 3-4 years ago when everybody, except me, only digged goa. The first couple of "Future Trance"-compilations were great representatives of this kind of music. At that point of time these were the people who were "selling out" on electronica, so it got a negative ring to it. Today everyone of them is almost erased by the maelstrom of time but they have been replaced by the likes of "Aquagen" which goes by the term "Club", which is basically Disco with a firecracker up its ass.

Gigi D'Agostino is too versatile to be categorized, as he produces both mediterrenean progressive like Picotto ("Bla Bla Bla", "Tekno Jam") and genuine pop ("Your Love", "Another Way", etc.). I reckon that he is one the great musical geniouses of our time though, and if you haven't heard it yet, try "Music", and then tell me what category this gem belongs to.