I'm not a big fan of itunes, mainly because the sync function is badly designed. I don't want to delete all my photos/music/apps and replace them with the ones in itunes. I want to append it manually, however if this option wasn't clicked originally you have to wipe all your data off the device and start again manually.
For instance I wanted to add some photos from iphoto to my phone however when I went to sync a photo album itunes asked if it was ok to replace all the photos in the phone with the photos from iphoto. No I did not want to do that, I wanted to have the old photos still on the phone and to add the photos from iphoto. Would I tunes let me do that? Not that I could work out.
The problem with apple is that all there manuals and help are sparse and incomplete. All the features are hidden until you have to search/google them.
I like some apple stuff like Time Machine and OSX but alot of it is complete crap, like apple tv, ipad, itunes, airport express.
