1) Lose the hideous flag icon. Maybe make it a blue or green dot instead of the black dot... or a square for the color blind so you are still signifying what thread/posts are unread but it doesn't look stupid.

2) Change the tab order of the 'reply' page. When you are viewing the post the subject should get focus and then tabbing should take you to the message body next and then preview/post after that. This will be the most common usage. I shouldn't have to tab through bold, italic, underline, etc. before I ever type a single character in my message.

3) The left menu and the forum pages look like they came from two diferent sites. Change one or the other so that they fit more within the flow of the site.