Using the Blogger Comments Feature
Blogger enables three ways to write comments. One is by logging in with your Blogger ID. Only registered Blogger users can make comments and that way you can know for certain who is writing the comment. It requires no intervention on the blog owner’s part and should resolve the problem of spamming.
The second method is that only members of the blog’s team can write comments. Basically it amounts to an elite pre-approved white list of users who can comment. The problem with that is it is extremely restrictive in the number of people who can leave comments.
The third method allows anyone to comment by using the “anonymous” option. This is the most inclusive feature of the bunch and does not restrict users in any way. Unfortunately, that is the method spammers use and anybody can leave a comment with complete impunity. Not to say that all anonymous commentators are spammers of course. It just means that anybody who is not a Blogger user can leave a comment.
That is perhaps where Blogger blew it. The commentor could be required to leave a name and email address, but unfortunately that can be spoofed very easily and doesn’t work. On the other hand an anonymous user could require the pre-approval of the blog owner first (thanks Lydia for the idea). However, the only problem with that is if there is a huge number of anonymous posters it could be quite time consuming dealing with it all. Nevertheless it might be an option that Google could consider in the future.
So if spamming is a real concern, you can always get rid of the “anonymous” option altogether and use the first method mentioned above. But your blog will be limited to only Blogger users and in effect become a billboard advertisement for the blogger service provider (i.e. Google - clever aren’t they :).
Not a perfect solution, but then again what is?