The deal breaker (for me right now) is that you can only get the S4 in 16GB where you can get the S3 in 16,32,64 GB versions. For a phone of this caliber 16GB is a "no win". I understand you can put a 64GB micro in it but only so much can go on it. Hell, 6 GB of the 16 GB is already eaten up by OS and bloatware. (YES, I have the Note 2 that only has 16GB of onboard storage....that is what I don't like about it)
Now if they offer a 32 or 64 GB S4 then I will likely get one.
Did the S3 start out only being offered in 16GB? Does anyone remember?