How long will iPod Touch 4th Generation receive support?

With the release of iOS 7 on the 18th, update support for the iPod Touch 4th Generation was left behind. I understand that it isn't a very powerful device compared to the new ones that have come out after 2010. It's A4 Chip and 256MB of RAM just won't cut it. I understand that it's an old device as it was released in October of 2010. I'm just wondering how long it will still recieve app support. What do you guys think?

~~DavidFromWinfield