It's more functional, which is always the most important thing. It seems a lot simpler than the previous versions.
This is by far the easiest to use. The best looking version was back in 2010 when you hired someone to design the website.
I noticed the mobile version is missing things like who posted last. If that's due to the width limitations, you should really try abandoning the use of tables. You should take up a more module design like you have on the home page. Do what Pinterest does. You can even do what I do if you want a better way of displaying topics / forums on mobile. Module Topic Example
I realize this is your first mobile friendly version, and it's a great start. In the future versions of this website, if you really want to put time into it, you should try doing what Google set out to do with their Material design for Android 5.0+.
From what I understand, their goal was to make everything look the same, regardless of what device or resolution you were on. If you're smart about your design, you don't need to program two different versions of a website for mobile and desktop.
I would stay longer and say more, but this Xbox I'm on doesn't support adblock, and I don't have the patience to keep swatting these ads away.
...You really should put a login section on your interstitial ad popup. Give it some purpose relevant to the website.