We've just added a captcha to the blog sign up process. It's unfortunate that we have to add security checks like this, but this will cut out any attempts at automated sign ups.

We did a lot of research on captcha before adding it to the sign up process. There are so many weak and/or unreadable captchas out there. We wanted to make sure that we had one that was strong yet still easy to read. I think the one we finally went with accomplishes both things. Every now and then I'll see one where it is somewhat difficult to distinguish a few of the characters, but you can just click on the captcha itself to get a new one that is, hopefully, more readable.

Many thanks to the OCR Research Team for their insight into weak vs. strong captchas and their own implementation of captcha, tEABAG_3D, that we ended up going with.