Ok everybody here is a solution to use with iOS 8.0.2 until Apple fix this with an update.
BEFORE wishing to sync over wifi with iTunes from your iPhone, turn your iPhone off completely...Then restart it up.
Then connect to your usual WiFi network on the iPhone, then open up iTunes on your Mac etc.
Now you will see that iTunes will find your iPhone with no problems....
This solution is only temporary as approximately 4 hours later on if you try to sync wirelessly again with iTunes and your iPhone you will sadly discover that iTunes no longer finds you iPhone, in which case you will need to shut down your iPhone again and then restart it, make the wifi network connection on your iPhone and then open up iTunes again on your Mac
Not ideal i know.....but apple are working on it....
There is no need to Backup/Restore iPhone/Restore Backup data process...it will not make any difference and does not fix this problem which incidentally affects iPhones predominantly and only some iPads.
Of coarse you can simply continue to use the USB cable option to your Mac from your iPhone which works fine with no problem. But here i was just trying to address the WiFi method with a temporary fix. Cheers everyone...!
Hope this helps everyone.