I have had the iPhone for a week now. I was going to keep it for a month, but I now see that it would be a waste of a further 3 weeks. IMHO the iPhone 5 is very close to its predecessor, the iPhone 4S. As previously stated I had swapped my iPhone 4S for a Galaxy S3 because (for me) it was a better phone. Nothing new that I have seen from the iPhone 5 changes that opinion.
I have supported Apple through my previous purchases of iPhone 3GS, 4, 4S, MBP, Apple TV, iPad and 2 iPod classics and was really hoping that this new iPhone would blow the competition out of the water, hell even if it was close, I would have forgiven it its shortcomings and gone with it because of my reliance to the Apple ecosystem. I really wanted to like this phone but can't, as good a phone as it is (and it is a good phone) I enjoy my S3 better, nothing has changed in that regard.
I am not technically minded and have not jailbroken or rooted any of my phones, I just find that even with a basic knowledge, one can customise (in minutes) the S3 to ones personal preference a lot better. I think I can sum it up like this; If both phones were TVs, the iPhone 5 would have a smaller screen, which in some cases isn't too bad, but tellingly, it would have fewer channels.
I think that there are a lot of myths spun when it comes to Android phones that might have been true in the past, however, IMHO, these tired old arguments are continued to be used by people that have not experienced the newer generation of Android but want them still to be true, or have spent only a couple of minutes using a shop display model, this is a shame, because those opinions nearly influenced me to not even bother with the S3. But I did, I bought the S3 and expected to be huddled over an instruction manual with a slow buggy phone that I couldn't get to work satisfactorily, and even when I could, the battery life would have been so bad that it would not last the day out. My experiences are the complete opposite, and convince me that some are blinded by a misguided loyalty to a single company or phone and would do well to sample other products and then to comment, good or bad. Some may be surprised.
I have the opportunity to pick from what I regard as he best two smart phones on sale at the moment. I have them physically to hand as I type, my decision is not based on others comments, but my real life experience of both phones. I will be selling the iPhone 5 and keeping the SGS3.
All the above and previous posts are of course, just my opinion and are how I use and want my phone to work. Both the S3 and iP5 are superb phones.