I dont use a whole lot of apps but I have a lot of music and pictures so would the 8GB be good for me?
If you can effectively use cloud storage - and the Nexus 4 is built for that - then yes, the 8GB will more than suffice for your needs. With automatic uploads supported by Google Plus and Dropbox, this is a no-brainer. Cloud storage not only reduces your need for local storage, it also makes your files available everywhere on any device with an Internet connection.
Despite what you'll hear, the 8Gb model is basically useless out of the box. In reality it has a little over 5GB available storage.
Despite sounding related, the two sentences in the above quote have zero to do with each other. Yes, in reality you will have a little over 5GB available for storage. No, that does NOT make the 8GB model "useless." If you need the storage, or you are the type of person who gets worried about storage (whether for good reason or not), then fine, spend the extra $50 (+ tax) and get the 16 GB model. But if not, and you never use that space, you just basically wasted $50 + tax.
It will also be easier to sell.
This is actually the only legitimate argument for anyone who doesn't actually need more than 8 gigs of local storage to get the 16 gig model. Yes, the 16 GB model will be easier to sell; it will have better resale value. That, however, is only relevant if you actually plan to sell it in a window that will still have a relatively high price. I plan to keep my phone for two years or so, and I probably won't really sell it even after that and keep it as an extra device. The saving this device plus the T-mobile $30 Monthly4G plan gives me more than pays for a phone.