I have assorted feelings on the matter.
On one hand, The game might as well be live if all the information about it leaked. On the other hand, to think that no information will be leaked is just naive. The "premier sites" like alla, wiki, etc can all take a firm stance of "We're deleting, nuking, and banning for any leaked information" but unless SE is going to go as far as banning people for it, that's not a huge inhibitor. And even if they were, who is to say that some poster named Mikhalia on Allakhazam.com also happens to be Mikhalia on FF14 Alpha? What's to stop you (someone who got in) from making a character named Mikhalia, I post "Hey I got in to the Alpha test! I'm playing a Sorcerer, and the magic cast system has a cool minigame that works like paper-rock-scissors and you can get damage increases!", then all of the sudden, you get banned when you did nothing wrong.
Beyond that, while the premier sites have agreements with SE, there's nothing stopping someone who gets accepted from posting something on Youtube/Livejournal/Facebook/Twitter/Myspace/4chan/Reddit or even their own personal website, complete with pictures and charts and everything? Honestly, even if SE were to go to the administrators of the site and say "Please remove these posts, they are in violation of an NDA", the NDA is between SE and the person posting the leaked content, and that's where the violation lies. SE can't sue (insert social networking site here) because one of their users broke an NDA, the best they can do is ban the user from FFXIV and ask the SNS nicely to take it down.
Would I personally leak any information if I got in? No, because I'm not going to risk it. At the same time, do I expect information to be leaked all over the web? Of course I do. Alpha goes live on the 11th, I'd be surprised if it took as long as the 12th before pictures and video and descriptions were publicly available.
"Closed" Alpha/Beta doesn't mean closed unless you have all your players in a room with a LAN disconnected from the outside world with no cameras or phones, and even -then- there's still word of mouth. I know two people that got in to the Alpha that I found out about over an IM, and I'm sure that if I really wanted to ask, I could.
So the NDA doesn't exclude anyone from saying anything, it just means that less people will talk about it, and you'll have to go hunting for conflicting information based on perspective, as opposed to having one source of accurate unbiased information. I think SE would be doing themselves more of a service by just publicly releasing the information themselves, rather than leaving their game to be virally marketed in a semi-restricted over the course of the next 6 months (give or take).
Personally, I'd rather see an official release on Alla about changes as they happen than have to read through an individual account of "This is my character" "This is me casting Fire" "This is me talking to an NPC". Don't care.
Besides, considering SE put zero marketing stateside into 11 compared to the advertising budget that Blizzard sunk into WoW, If SE is confident in the quality of their own product, why -wouldn't- they want to promote it? Sure they have a built in player base of people who want to "move on past 11" and people who quit 11 but "Hope 14 is better" as well as the inherent audience of "It's a FF game so I will play it", but why not move past that? "Is WoW boring the everliving **** out of you? Are all the WoW clones leaving you feeling like no one does anything original anymore? Try FFXIV!" would easily drum up a lot of buzz about it. ****, I went into game stop to get Miles Edgeworth and put a preorder in on FF13 (and the fiancee put 5 bucks on the new Pokemon)... there's FF13 ads plastering the front of the store. Put that kind of marketing into 14, ffs!
It's just like Fight Club. You can say not to talk about it, but breaking that rule is the main thing that leads to growth. I'm not advocating breaking whatever rule you like, whenever you like, but SE's "First rule of Alpha: Do not talk about Alpha" is more likely to hurt than than help them.
Mikhalia: and FWIW, my posts are 95% helpful, informative, or funny.
Mikhalia: only 5% or less of my posts are utter crap.
Tyapex: 393 posts of utter crap...
Mikhalia: Sounds about right.