I'm sorry that this jarred you, we posted a notice there well over a month ago letting folks know that the site would be closing. I probably should have moved a recap of that here once the site redirected, and I'm noting that for the future.
You'll soon be able to access all of the content, we'll make a data dump available that you can download from the page you were redirected to, the site's proposal page. We should have it available very shortly, I'm going to check with our developers to see if we can expedite making it available when they arrive later today.
The site was closed not because it lacked activity in general, but because the community that once started it had for the most part left, and wasn't being replaced with new people as folks found the site. People would come and ask a question, and we generally never saw them again. This left the tasks of actually caring for the site almost solely on the shoulders of the moderators, and there was no good way of fixing that.
To put it in perspective, for a long time, only one person was closing questions because the people in the community that had the ability to do this weren't there. It was also only two or three people making decisions about topic guidance, tags and taxonomy and other very important things that should be falling on a group of at least a few hundred. Quality began to really suffer, broken windows started lining the streets. Once a site reaches that point, it needs to be closed and re-focused if it's going to work.
That's why we announced the closure on the site, and told folks that they'd need to put the topic back through Area 51 to ensure that it had a sustainable community behind it before trying again.
To recap, the site had quite a few daily visitors, but very few of them actually realized that there was a broader community behind the site and participated much behind asking one question. There were plenty of high rep users, but many had not been seen in well over a year. There were lots of questions, but many of them needed closing, and only a few people that were left could close. That didn't make them very popular, to say the least.
Those that stuck around and diligently shared their knowledge by answering questions deserve a better site in which to do that, and one can quickly emerge if enough of those folks want to commit to a new proposal. The old one, as closed, was just blocking a much better and healthier site for the topic. This wasn't a decision we took lightly and we did delay it several times. Ultimately, we think it's for the best to try again.