I would love an updated edition, but not sure. The game description reads exactly like the WWI Gold description on Matrix site. Could be the exact same game relabeled?
Correction: The game description is the same on GamersGate, but Steam gives the new details. I'm tempted, but after paying for WW1, WW1 Gold, I've had enough.
If you feel like you saw all WWI Gold had to offer and weren't taken with the game play, then I'd definitely pass on CE. But if you feel like you never really got to experience the game because the performance was so bad, then CE might be worthwhile. The performance improvements are dramatic.
WWI Gold, for me, was one of those those games that I wanted to love but just couldn't because the performance was so bad that playing the game was a beating. CE fixes all that, so I finally feel like I'm playing the game as it was meant to be. I think it's now the best WWI game on the market, by far.