We just started using a Captcha image recognition solution because the amount of form submission spam we were getting was just ridiculous. It has of course cut it down to zero and people are still using the forms to contact us.
I figure as long a the image is easy enough for humans to read, personally I have no problem filling in the code from an image. If someone is so lazy that they can't fill in the code from the image, I don't want them contacting us anyway.
We also had to kill the Mailform.cgi as people can use that whether you have a form on your site or not to not only spam you but to send thousands of spam emails through your server.
I believe that image recognition will become more common-place as time roles on. It is simply one of those things we have to put up with thanks to spammers.