FWIW (and it may be worth nothing), I'd never use the SD card for apps on the GS3- just photos/music. With the large internal memory, I'd use that for apps simply because of the amount of reading/writing that will be going on constantly. It seems like if anything will kill an SD card more quickly, that would.
There's also the speed factor- why would you want to slow down your phone by forcing it to do constant reads/writes to slower media?
I do understand that some of you probably have tons of game which eat up internal memory fast, so I can see why you might want to use it for app space too.
And always have a backup of those photos & music- forget the SD card issue- who knows when your phone is going to just completely crap out!