As I have been doing the WGSJ, where I would come back on to the site over, and over, I'd get the captcha request all the time. (I had exceeded my log on attempts in too short a time.)
Just this morning, getting on right now, it happened, and I hadn't been on since yesterday. So, yes it may be nefarious because it does ask you to register if you are not a member.
The captcha is always the same question, and a slightly tricky question since it requires a possessive answer.
However, this is hardly the security scare that really scares me. The one that really scares me is when I have cleared out my History on my Mac and instead of coming in through Yahoo!, I try to come in through the top of my Mac type-in section. I type r, then u, and it will start to self populate, and I'll see rukind of some sort show up, so I'll click on it. And a warning page will appear that the site I am about to enter is not a secure site, and is pretending to be rukind. It asks the question, do I want to continue?
So, I just close everything down and maybe even clear some more History, and then I come in through Yahoo! in the more familiar manner.
Whenever I look at the bottom of a page at this site, when I'm logged on, to see whoever else is on, I always see things like Goog [Bot] (or something), and someone else (a real user), and 0 or 1, or 2 guests. So, there are security concerns, and you just have to be vigilant, and take a little personal responsibility for your security by using common sense, and by going the extra effort to insure that you have gone far enough.
Friends have told me, just general knowledge for the Internet, to clear your computer's History every night. Maybe not a bad idea.