I don't know if this is a persistent issue or not but I find a lot of spam these days. I won't suggest using CAPTHCHA so maybe a more effective report system or a 'Digg' system to bury bad posts?

I think there's a lot of attempted spam on here that you don't see. we should be thankful ;)

There are mainly four ways we get rid of spam:
1. lots of helping forum moderators who manually delete stuff
2. an ever growing blacklist of words or phrases, which I add to daily to weekly
3. a "soft blacklist" which merely triggers a lazy-CAPTCHA (you will just be required to add up two numbers)
4. a hidden form field which, if you fill it out, will block your submission as it's probably bot-submitted

In general, the good will of all of us here is what keeps the forum good as well – the better our discussions, the less spammers (or trolls) will think they can abuse our place!

YouTube's blog is doing much worse:
http://www.youtube.com/blog?entry=4qHaGXFt82E

I like the hidden field idea, I hadn't thought of that before.

The description / text for the field for users without CSS was also a good idea