The commentary is a little below average and he seems rather new to the game, but I want you to pay attention to the camera and not the guy behind it. The Grove is absolutely stunning and the bioluminescence of the plant life almost parallels the beauty of James Cameron's Avatar. Personally, I am overwhelmed with the redesign for the sylvari, and am extremely excited to play them. Many people have said this, but I feel it's significant, that I have never, not even once, been attracted to play a "plant-like" race in any game. However, ArenaNet has worked their seductive magic and made me fall for something I would never have expected. Well done, ANet.
More videos after the break.
Note: Something interesting I noticed, and I think this is true all the way back to the convention footage, but some of the skin tones for the sylvari are quite human-like. I would love to see what it might look like in-game.