Originally Posted by Tilt2turn
I didn't see a message for the new update either on my iPhone 4. So I went to Settings and when I looked at the Software Update, it stated that I needed 2.5 gig of free space. I had 1.1 available, so it wouldn't let me update until I cleared enough off of my phone. After that, no issues with iOS6.
That is probably my problem as well. I don't have that much free space. 2.5 gig of space for an update.