Ofcourse some sort of captcha is necessary. If you are bothered about the looks, then the real question is what kind of captcha should you implement. You can go for the audio only captcha , or perhaps even a flash based visual one.
Repetitive captcha tests can be avoided if your application limits the frequenzy of submissions made . But this in turn is a larger annoyance for commenting systems.
Repetitive captcha tests can be avoided if your application limits the frequenzy of submissions made . But this in turn is a larger annoyance for commenting systems.