Installed 1.1.3 no problems then a day later upgraded to Leopard. However now when I connect my iPhone, it doesn't show up in iTunes. Can still import photos via iPhoto so mac is seeing the phone but just not in iTunes.
Did this and it fixed the problem. The first time it synced after took ages, almost to the point i thought it was hanging, but waited a bit longer and it completed the sync, now when I do it, it syncs as it did before no problems. Hope this helps you.