I'm sure anyone who has their own Blog, or has even come across someone else's Blog, would agree that comment spam can be quit a nuisance. Google has recently announced their idea for how to prevent such abuse. Google's idea is to add a new attribute to "any [hyper]link that a user can create on your site automatically." Google claims that when their spiders see hyperlinks with the attribute (which takes the form rel="nofollow"), they won't give any credit to the links when they rank their search results. The thinking is this will eliminate the benefit the spammer would gain (higher ranking resulting in more page visits) from posting such links. Having a high ranking result for a search can mean a lot of traffic, and so a lot of revenue for any site.

While this solution may very well result in lower page rankings for spammer's sites, it doesn't seem to solve the problem of your Blog getting spammed. Also, this seems to work directly against one of the greatest (and inherently brilliant) features of Blogs, Forums, etc... As they grow they automatically build vast, interconnected bases of information on all sorts of topics. There are Blogs out there for nearly every topic imaginable, and while many may seem (and probably are) useless to you, there are also those that you (or someone) will find very valuable. The great thing is that when you find one Blog (or forum post, etc...) with information you need, it will usually point to to more resources along the same topic. Sound eerily familiar?  Perhaps that's b/c its precisely what Google's PageRank is designed to exploit.

So what is a good solution? As we've seen time and time again, there is no end-all-be-all, no magic bullet (err... piece of code) to stop spammers. They will continue to find ways to circumvent whatever measures we take to protect ourselves from their constant barrage of propaganda. However, to quote the old cliché, lets not "cut off our nose, to spite our face." I think that something like CAPTCHA is a much more viable solution. Most of those are for .NET, but there are CAPTCHA controls out there for all kinds of languages/frameworks. Well, I'm going to give it a try on my Blog anyhow.

Update: Since I'm now involved in the subText project, I'll just wait till I install it (soon) since some anti-spam measures have already been implemented.