Thank you for helping us by reporting bad content.
I wouldn`t say that it`ll be thinner. After all, it is already 7,1 mm thin. That`s insanely thin!!
But I`d say, don`t wait, even though because it`s only a matter of a month or two, and if you buy one now, it`ll be outdated in 2 moths, and the apple store won`t have accessories for it anymore, plus then it`ll be 1 year closer to apple discontinuing support for it. I know, that sounds scary, but jump to the end to know why i wouldn`t wait. Now for the rumors:
From the rumors I heard, the ipod touch 5g will have a bigger screen (like iphone 5). Either 3,7 or 4,0 inches.
It will most likely also have the A5 processor, found on the ipad 2, though I`ve heard apple is having overheating problems with the iphone 5 test models, and might still keep the A4 for the iphone and ipod touch 5.
The display resolution will most likely stay the same, will the screen get bigger or not. Apple has ordered glassbenders, suggesting the 5 devices would have a curved glass, like the one found on the nokia N9.
The camera is also suggested to be better on the ipod touch. Autofocus is unlikely, if they want the device to be as this as it`s now. But they have said that the back camera would have a resolution of 2-3.15 megapixels, so nothing too interesting, and the front camera would stay the same.
The iOS 5 has traces that they would get rid of the homebutton with new gestures to replace it. But, only maybe in ipod touch 6, as foxconn has sent pictures of the iphone 5`s front glass, and it has the hole for the button.
But then again, you never know about rumors, and here`s the big blow up of your dreams of all those, the iOS 5 also has a list of supported devices, and the code number for the future ipod touch is 4,2. This means that only the second number has changed, meaning that it will most likely be just a small upgrade. If it would be big, it would change the first number. This means it`ll maybe be just the camera. Or the screen. Nothing else. Just an update.
I wouldn`t wait, because it will most likely be a small update only. Yes, then it`ll be the new one, but it will, be NEW. And that`s the problem. It might have things witch have gone wrong. It might be bad in some way. The ipod touch 4g is under a year old still, but it`s tested, people have it. You have reviews. Compared to the 5g, there`s none. Only what apple has done. If i were to get the 5g, i`d wait for a few months after the release before buying it, to be sure it`s good.
And I am sorry for the amount of text. I like to write :D You be the judge, do what you want. This is what I`d do, but then again, who am I to know what Apple, the oh so quiet about their plans is going to do. I hope you can figure it out! :)