How does this version of CE relate to the oringinal eon version, is it just a modern revamp?

Simple answer, it is not a direct reprint but I guess you could call it a revamp.

More complicated answer is that the game mechanics are essentially the same as previous versions. The FF version has 5 players and 50 aliens straight out of the box, some of which are new and the others are trawled from the previous incarnations of Cosmic. You get "flares" as part of the standard game -- these were in expansion sets in the Eon version. And the FF version also has "technology" cards.

See this thread from board game geek: http://www.boardgamegeek.com/thread/361426

There is a nice review summary of the aliens here: http://www.boardgamegeek.com/thread/365587