Doesn't seem like a lot of thought was put into layout or functionality. I only use desktop so can't comment on any mobile optimizations.
You can only see 2-3 different discussions at a time on the screen even with a large monitor. This causes you to need to do an awful lot of scrolling to find a post that interests you. I would recommend significantly scaling back on how much of a post you can preview without clicking on it so that you can see more posts on the screen at once to more readily identify posts that you actually want to click on and read.
The fact that you can only see 2-3 different posts at a time is compounded by the fact that advertisements are included in the same general space. Ads could easily be moved to a sidebar area where they could remain static and always visible while you scrolled posts in the main section.
Hovering over the forums tab at the top doesn't provide any sort of breakdown of sub categories like the education and network tabs do.
Clicking on the actual forum categories button pulls up a list of categories that involves significant scrolling to see what options you have available. Real estate isn't rocket science, I should be able to see all of the forum categories on one screen without needing multiple full scrolls of the mouse wheel to scroll through all of the different categories....
Which leads to my next point, there are WAY too many forum categories, many of which are HIGHLY redundant.
You have a "general real estate investing" which is separate from your "general info" subcategory.
There is an "investor deal diaries", as well as a "completed deal diaries", and a "rehab diaries", and a "success stories" and a "not so success stories"
"Rookie investing" as well as a "first time home buyer", and a "starting out".
"Real estate events and happenings", and a "BPCon attendees", and a "BP real estate investing summit"
"Housing news and real estate market discussions", and a "real estate news and current events"
I could probably find other many examples of redundant categories, but you get the point, many of these categories are redundant and would be better off merging them together to create a more unified experience. Additionally having links to the various podcasts inside of the forum categories further clogs up the searching since forums and podcasts are two completely separate products.
Some categories like BP con 21 are completely irrelevant since the entire event is over, other categories like the investing summit category only have 4 total posts. Other categories like Real Estate Quizes sounds like it should be something in the education tab and not in the forum tab, not that it really matters since there isn't even a single post inside the real estate quizes category.
Podcasts are a big enough part of what this site offers that it deserve its own tab at the top just like forums, education, and network have instead of burying it in the education tab.
I could probably go on with other things I dislike, but in general someone needs to put some serious thought and effort into the layout and functionality of the desktop version of this site. As it stands it looks like a product that was created by paying some guy on Fiverr $20 bucks and he used a generic wordpress template.