Just fixed the decimal places in the list view for the next beta. I caught it everywhere else, but forgot about the list view.
How much of a delay are you seeing? A 0.5-second to 1-second delay is expected, considering the amount of images and data that are displayed. Obviously there's more information displayed there now than ever, so it makes sense that it might take slightly longer (though loading the achievements should be threaded so it shouldn't significantly delay loading up the information).
Early on in this beta I also fixed some flickering issues when loading up the details as well, so that might be what you're seeing. Previously as the game details sidebar was updated with new info, the presentation would flicker back and forth a bit, which it no longer does. Now it waits until it's actually ready to properly display the info before updating it. It's also more multi-threaded now, which of course is going to favor newer CPUs with more cores.