With the latest iTunes 10.5 and above, you are able to sync wirelessly with iTunes via Wi-Fi. This means that if you have just created a ringtone for your iPhone 4S and is docked or charging somewhere else, you can transfer to your iPhone 4S. This is tested on iPhone 4S, iPhone 4 and iPad 2.
First and foremost, iTunes can only do WiFi Sync if your iPhone or iPad is charging and/or docked.
Second, you have to initially plug-in your iPhone or iPad before WiFi syncing can be done.
Third, setup what you need to sync and to do this, in iTunes, click on your iPhone or iPad under devices. There you will find tabs, such as Summary, Info, Apps, Ringtones, Music, Movies, TV Shows, Podcasts, and Photos. If you want wireless sync to work, you have to enable what you want to sync so in the future, iTunes will look to wireless sync what you selected from the Tabs. The more you have selected to sync, the longer it will take to sync.
Fourth, setup the wireless sync in iTunes. If you already have iTunes open, under Devices, click on your iPhone or iPad and under the Summary Tab, scroll down to Options and there you need to tick on the box “Sync with this iPhone over Wi-Fi” if you have your iPhone plugged in. Once that is already setup, do a test by keeping your iTunes open and charge your iPhone or iPad. You will see it in iTunes and syncing whatever changes to the pertaining selection you made during step two. If there is nothing to update or if it finish updating, your iPhone and iPad will disappear from iTunes indicating that it’s done syncing.
Even if you are behind a corporate firewall, it should work. It works for me, and as the above screen shot showed that I have Photos to sync wirelessly to my Mac Book Air and sync Apps from my iMac.