Log in to the Forums and then click on User CP in the upper-left corner. This is your user control panel. Once there, look for this link...
Spam Prevention In order to reduce the amount of spam on your blog the administrator has provided the option to provide an Akismet key. Wordpress API Key:
I think the only place you can get one is from Wordpress. There is an option to set a global Akismet key so that everyone can use it, but I don't know how to get one. I am pretty sure that the only place to get it is from Wordpress though. If spam becomes a problem then I'll find out how to get the global key.
I've seen posts about people having problems with the Blogs. It doesn't seem like anyone is using them very much either. Are there problems with them that need to be fixed?