iTunes 11: Any guesses on what is delaying the release?

I know Apple has until the end of the month to release iTunes 11 so this is an innocent question since and I'm not rushing them. But what do you think is causing the delays? Executive reshuffling? Weak execution? Bugs? Features? Windows version holding back Mac release?

Also, is this the "Major Overhaul" that was reported back in June? And, based on the little info we have since Apple didn't do public Beta's, do you feel it will deliver?

Apple - This is iTunes Like Youve Never Seen it Before

Verge - iTunes Overhaul Coming

As someone whos always been an iTunes user but never really an iTunes fan then I'm pretty excited to see an update but I also dont want to get my hopes up if this is more about cosmetic changes rather than a true overhaul or rethinking of what iTunes should be for 2013 and beyond.