On the old forum you had the Tapatalk plugin installed; every time you visit the forum from a mobile browser is does one of those annoying Javascript system() popups (like the Alert! boxes that you can make popup on Windows) that says to install Tapatalk. Tapatalk is a $4 app that is updated pretty frequently, and the updates aren't free; every time they decide to upgrade version numbers (from Tapatalk 2 to 3, 3 to 4, etc) they publish it as a new app with a $4 pricetag.
And on top of it all the app isn't very good.
Basically, what I'm trying to say is a regular mobile site would be much appreciated. I (and I'm sure many others) browse the web on my phone and tablet a majority of the time, and it'd just make it easier to be able to view the website in a browser with a mobile-optimized layout.