Devices that might receive iOS 7 update

Ios-7_medium

Obviously all A5/A5X/A6/A6X devices will receive iOS 7 without no problem. But what about A4 devices?

There are three devices which use A4 chip: iPad 1, iPod Touch 4th gen, iPhone 4.

iPad 1 was already eliminated on iOS 6. In my opinion ipod touch 4th gen won't receive the update because of 256 mb ram.

iPhone 4 will receive it. But there may be lots of removed features. And I expect some lags on ui and crashes in apps while running iOS7.

What do you think?