The Web != Usenet. This is a web forum.

I chose to use a web forum over a usenet group as it is much more readily accessible. Readers of my website can click a link on the main site and view the forum immediately. Other websites can link to specific threads.

The user thus does not need to download and install a news client, configure it to read my forum and then download the headers. I could neither explain this simply enough to others, nor could other websites link to the forum easily. Using usenet just puts a needless barrier between my website readers and joining the discussion on the forums.

You managed to post your question with next to no effort; does that not answer your own question? :)