First off I think it's funny you you stated for the US, but used the British-English spelling of color.
As for the green DSi, I have it, bought it here in Japan, and I must say it gets a bit hard to look at after a while, wished they would have gone with a bit more green than they did, a bit too yellow-green. It does look nice, but the black one looks the nicest. I just wanted a color I couldn't get in the US and I didn't want to wait for the KH one to be released, and white gets too dirty.
Also, you can't go wrong with an Acekard 2i, mine plus my DSi equals WIN! It's so easy to carry and I can even load a few songs when I don't want to mess with my iPhone. Plus it's not as bulky as my PSP, though I can do more awesome things with it. Just having all the games on a single MicroSD that stays in the DSi is just awesome, allows me to carry many games without carrying a pocket full of carts. Also I was able to self-translate a Japanese RPG so I didn't have to deal with the English dubbing >