Two of the most common message board software providers are UBB (that we used to use) and vB (that we currently use). The formats of both of those are very similar in general appearance. (And, of course, if the NA board is using vB, it will be nearly identical except for the colors. I’m pretty sure that that site is also using vB. They permit, while the SDMB does not, “avatars” (little pictures under the username), and they use (while the SDMB does not) a system of suspending a post until a moderator looks it over to see whether it is “appropriate.”)
As noted above, we have been subjected to “invasions” from some of their posters, since we are (in their view) a “liberal” board. Their members are welcome to post here, as long as they are not trolling or otherwise being disruptive–acts which got a few of them banned from the SDMB. Similarly, you are free to register and post there–but will probably lose your posting rights, here, if you make a point of declaring that you are “from” the SDMB, since we really do not want to encourage board wars.
The National Alliance (for which they are the web presence) is another odd group of people who actually believe that there is some sort of (poorly defined) “white” race that is “under assault” from people of color. Their science is non-existent–claiming, for example, that somehow Jews are not “white,” despite the fact that Jews were clearly grouped with whites/Caucasians from Linnaeus to Shockley.
My advice is to be aware that such people are out there, but don’t spend a lot of time encouraging them and spend no time attacking them.