I'm with MG23 - always wait at least a week before updating.
The first couple of days Apple's servers are overwhelmed and you get things like "9 hours".
Any, even minor, fault will be over-reported in the press. You, and everyone else, will be well aware of all of Apple's 'failings'. Apple usually fixes these quite soon.
So, if things remain quiet (well done Apple) I'll upgrade next week, even if we haven't seen 10.1.