Hi there, I've been following the other thread about the subject on the iPad for and did some reading on here too.
Taking into account what the Genius said to you, Rick7, and your suggestion about the problem being memory related, I did some tests on my iPhone 4s. I'd definately say that the problem is memory related. At first I tried simply switching on the Refresh on the Background setting, to no avail. Now take into account that I consider the problem rather severe in my case. Almost any action, switching apps or going back a page in safari takes a refresh.
After thinking the problem is memory related, I tried switching off my device, which as you knows frees up a lot of RAM space. And how about that. No refreshing whatsoever, at least not by Apple apps (maybe your genius was right about the setting in other apps, as an extra to the problem.)
As the problem doesn't occur on newer devices, I'm rather worried we'll never get a solution.
Because honestly, Apple has not been the top dog in keeping older devices compatible.
I'm right here hoping with you guys, but I know for sure that in the time coming I'll be switching my iPhone off a lot more!