I'm one of few who will say this, but if you are going to get an Amex charge card that's NOT the Zync, go for Platinum. Zync is your first step into Amex, not sure why green and gold are there. Green and gold's reward system, when converted to monetary value, is not as good as other general travel cards (Sapphire Preferred, or even Venture cards), and even worse compared to Airline/Hotel-specific cards. I'm a statistician, so math is my thing - I spent a lot of time doing math on the reward redemption system for Amex, and it just not worth that much.
If you haven't already, read this thread:http://creditcardforum.com/american-express/4601-why-do-you-have-amex-gold.html
Basically, the take home message is people get the Gold just because they like it. Not because it's good in any particular way.