I asked the Q&A associates their opinion, and several people also responded that a 503 would be the way to go.

Can you give us some more details about the shutdown (the reasons, why it needs to be so long, etc)? We can help you a bit better if we know more information.

When we switched from SEOmoz.org to moz.com, we were only down for half an hour, if that. If this is about upgrading, is there a testing server that you can use to get the website rebuilt and tested on the testing/staging server before you make it live? We used multiple staging servers to test out the site and did lots of checks so that we had minimal downtime when it came time to move the site.

Could you include your URL? That could help us out.

I've had some filters block access to strikemodels.com presumably because of the "models" in the URL (it's actually model warships), but haven't had a problem with Google filtering it out.

You've got the right approach there. We do our best to look at the web like Google does, but we don't have quite the resources they do. We do have to make tradeoffs between getting an index out in a more timely manner and getting one out that has a lot of data. The bigger we go, the more problems we run in to. This last index was about half the size of the previous index, which would account for much of that drop. So sorry to scare you!

I enabled safe search, then did a site:blackcupid.com search on Google. There are a lot of pages that show up as indexed, though I didn't see the home page right off. If I search for Black Cupid, I do see pages from that domain, but not the home page.

I took a snippet from the help page at http://www.blackcupid.com/help/helpcategory.cfm and searched for it in Google, with safe search on. Google is showing dozens of results from similar sites, such as Brazil Cupid and Japan Cupid (then I went to the home page and saw that all of those sites are indeed related).

How are the other sites performing? Do they have the same problem? Have you always had this problem, or is it new?

Any messages from Google in GWT?

And here's the place to ask that you site be reconsidered:

https://support.google.com/webmasters/contact/safe_search

Can you share some of the information that led you to that conclusion?

From a user's perspective, be sure to look at how the site will show up on a mobile device. Here's a great post from The Oatmeal about what users want vs what they get from a restaurant website in general. http://theoatmeal.com/comics/restaurant_website

Only the title was tweaked, making it apparent that there was no physical attack.