FWIW, the sync issue I had had seems to have not happened again... then again, my desktop never sleeps, it's either on and being used or off. OTOH, I'm still on Snow & iOS 6. Yes every now and then see the issue of iTunes NOT seeing the iPad... sometimes relaunching solves it, sometimes logging out and sometimes shut down & restart is needed. BUT it is VERY occasional.
Clearly this is a very intermittent problem, extended over different desktop OSes and mobile OSes, and one that IS very hard to pin down. As such, and as this is the Apple w/o Jobs, it's all about the money... so it seems they just aren't putting a whole lot of effort into really fixing it. It sure has no impact on those revenue/profit numbers or their ability to pile up all that overseas money.