I like (and recently ordered) a black model. The reasons are the same as have been discussed in this thread. The all black model is sleek and sexy.
If the finish and edges quickly begin to wear, the all black model is no longer all black. The problem will only get worse over time.
Yes, it is a small problem if you plan on having a case or just plain don't care. However, I won't be using a case. I will opt for the model that was intended to not be all black--because the all black model can't deliver.
----------
More Scuff-Gate evidence. iFixIt was able to make it happen!
http://www.ifixit.com/Teardown/iPhone-5-Teardown/10525/4
See towards the bottom: "Step 29"
Look at how you worded that: iFixit was able to MAKE it happen. Look at their photos - it appears that they used a FRIGGIN coin to scratch it!! I can just see the idiots now, sitting around trying to scratch their phones to "confirm" this "issue."