I never post to forums, but I feel as though it is warranted.
I, too, am having problems with my iPhone 4s after updating to ios 7. My wifi is greyed out, and my Bluetooth no longer works (spinning). I did my own troubleshoot. Further research revealed that this seems to be a massive problem for 4s users after they updated. Still naively optimistic, I worked with a couple polite Apple support folks to troubleshoot, to no avail. I refuse to put my phone in the freezer, refigerator, or put a blow dryer to it.
I was told by a very polite Apple support person that my phone is no longer under warranty, and that I would have to pay $199 for a replacement.
This is a story we've all read several times on this thread and/or other forums.
If this was a relatively isolated incident, I would gladly accept that my phone is out of warranty, that hardware is not perfect and sometimes fails, and I would pay for my replacement (or wait for my upgrade in 6 months).
This, however, is not an isolated incident. The connection between the ios 7 upgrade and massive wifi/Bluetooth failure is undeniable. I am not here to make claims about deliberate sabotage or planned obsolescence, as I do not believe Apple sought to fry tons of phones with an OS update. Who would? That's crazy. I am, however, here to add to the voices of dissatisfied customers that no longer have access to the most important feature of their phone, with no recourse but to pay for a replacement.
I will not pay $199 for a replacement. To me, it is not an accpetable alternative. I appreciate the help I got from Apple support personnel, but I will especially appreciate when Apple chooses to at least respond to this apparent problem in a meaningful way.
Thank you.