Do apps still close automatically in iOS 7?

I presumed apps would still close as they did in iOS 6 after a period of inactivity/other apps have replaced them, but as far as I can tell the apps stay open - I tried opening dozens of apps, and the first app, once re-opened, seemed to resume rather than re-open. I've now started closing the apps I don't use right now.

So, do apps still close themselves? Or is multitasking now more like it is on OS X and Windows?