The iFixit team said,
We delved inside Apple's 'refreshed' device and found the same components we'd seen in Touches of yesteryear, but with 16 GB of on-board flash memory. So it's not really that this 16 GB variant gains a camera — instead, it loses half of its 32 GB of storage.
That means the 16GB model isn't easy to open or repair, replacing one failed component often means replacing several working pieces because they're all attached, and the battery is glued in place.
iFixit didn't find anything new in the updated 16GB iPod touch other than a camera
Apple introduced the updated 16GB iPod touch yesterday with a rear-facing 5 megapixel camera and adding the full range of color options its higher capacity siblings offer. The company also dropped the price from US$229 down to $199, and lowered the prices of the 32GB and 64GB models to $249 and $299.
It isn't surprising that there aren't any other component upgrades in the 16GB model considering the 32GB and 64GB are unchanged. iFixit's repairability score for the iPod touch sits at 3 out of ten, meaning it's an absolute pain to repair.