Instead of one CAPTCHA you must enter, a site has two. The first one tests you against an answer the computer knows. The second is one the computer doesn't. It's not testing you; it's putting you to work. You're reading a word from an old book or newspaper that the computer can't decipher correctly. Instead of wasting your few seconds of time, you've invested it in a cause, helping put more printed works online.
I guess it's OK to call time spent playing Solitaire wasted time, as long as you don't say it about Spider Solitaire.
I find the new text hard to decipher, which is good from a security pov. Also, the system seems to hate Chrome.