Is zerocoin still being worked on? Last I heard the project itself was a great idea and was being worked on, but either didn't look like it was going anywhere or was abandoned altogether. This looks like it's the latest news and that was posted a month ago. The content of Peter Todd's comment is kinda disheartening as well that they will be trying to profit from establishing a business model around the coin.
I don't know about the status. Last I heard, an open source implementation was coming. True anonymity perhaps, but it's vaporware for now. I do know that there's considerable interest on the Namecoin team to use this. Namecoin is difficult to use anonymously - baking in anonymity by default would be huge.
For now, Darkcoin and Monero look like the leaders eh? For my money, I'd go with Darkcoin, just because I've always liked it, and because they keep improving and tweaking all the time. And we can easily keep up with their progress by reading the great articles here from @fernando
