If you have multiple folders dedicated to the same type of apps, such as 'Games', or in my case 'Social', they can now be consolidated into a single folder! Since the introduction of folders in iOS 4 you could only keep 12 apps in a folder on iPhone and 20 in a folder on iPad (this was bumped to 16 with the introduction if iPhone 5). Folders in iOS 7 now have no limit!
To move apps into a folder, tap and hold on an app until it wiggles, then drag it onto another app, and hold until the folder is created. You can now move apps into this folder in the same manner; make them wiggle and drop onto the folder.
As you can see here, my 'Social' folder shows only 9 apps/icons, but if you tap on the folder, it will expand.
When the folder is open you'll notice that the first 9 icons are the same icons that appear on the home screen, however there are two dots (or more depending on your folder) at the bottom indicating that the multiple pages in the folder. Just swipe left and you'll see the next page. Shown below are the two pages of my Social folder, with the page indicators circled.