I can guess. This site is based in WordPress technology. Normally a pretty snappy setup. However, the amount of customization of the site’s core functionality to make this site more fully featured is causing some delay. But I think the real big thing is the CDN or cloud services this site uses is particularly slow. The number of add-on scripts is also pretty large and as noted in the source rendered HTML, the scripts are pretty slow at over 1.5 seconds.
While using a CDN for storage is real cheap, it often results in slower performance for some sites. Depends on who your cloud provider is.
Also, and this gets nerdy, there are performance gains that could be had with the reduction of HTTP requests. This relates to all the images, scripts, and other page assets that are requested every time someone clicks a link. Small fixes like using image sprites could help. Then there is server caching. I’m no expert there but I suspect something could be done to cache the most frequently called assets to the local server instead of calling it from the Cloud every time.
So the nut of it is, IDO has a cool site with a lot of nice extras and those cost us all in a smaller delay in performance. Can you have cool AND fast? Yes, but that is probably out of the financial reach of a smaller media operation like IDO. I say enjoy the richer site, and be patient with a little lag.
Also, it is common for a newer Web application to focus on getting a fuller set of features released first and then spend a while improving its performance. ObamaCare ring a bell anyone? The last year has been billions spent just trying to improve its performance. Pretty standard Web app approach these days for most companies I have contracted with.