My iPhone duplicated my contacts?

I have an iPhone 4S for Verizon and I just upgraded to iOS6 yesterday. Today I went to back up my contacts and it backed then up as usually, but also duplicated every single one if my contacts. How can I fix this without individually deleting each duplicate?

Why don't certain features of iOS 6 work on iPhone 4?

I bought my 8gb iPhone 4 less than a year ago, and it hasn't been out much longer than that either. I just downloaded the new iOS 6 update and realized many key features, such as panorama photos, spoken maps directions and 3G FaceTime capabilities are not not supported on my phone, yet they are on the 4s, which is virtually the same thing with the exception of Siri. Why is this? Is there actually a legitimate reason, or is it just Apple's way of getting people to buy another phone from them?

Can I add memory to my iPhone 5?

I was very eager to get the new iPhone and my cell provider only carries the 16GB model. When I went to sync my music it pretty much took up all of the memory on the phone. Is there any way I can add more memory? And if not, is there something I can do so that my music doesn't take up so much space?

Private browsing in iOS 5 update for iPod, iPhone, iPad?

Apparently it means it won't save to the history. But I want to know if it will save to the computer or router my iPod's Internet comes from. For example, if I went to www.9gag.com, would it show up on the router or "master computer"?

Uploading Pictures to an iPhone?

Can someone please explain to me exactly how to upload photos from a folder in iPhoto on a MacBook Pro to an iPhone 4? And I mean step-by-step instructions because this technology is very new to me… All the info I've been able to find gives condensed half-answers and is useless.

Is it worth getting the iphone 5?

I have the iphone 4 now and i can upgrade soon. Should i buy an iphone 4s now and wait for something like the 5s or 6? Is it worth paying another $100 for the iphone 5? Is all the new features worth $100?
Please a detailed answer if possible.