New D800 - Help with settings

When I made the transition from D70s to D300 I found it took me more than 6 months before I felt comfortable with the D300 - lots more controls and a steep learning curve.
Having played with a D90 its a similar jump to the D800.

Just 4 weeks ago (4.5 yrs of D300 + D300s ownership) I was struggling with features / menus - the D300s Focus assist light wasn't coming on - and didn't know all the combination of settings that were a pre-requisite for the focus assist light to work (e.g. center spot focus has to be in the center... silly me).

The transition to D300s was very easy, and the transition from, the D300s to the D800 (did this week) was relatively straight forward - but its going to be many months before I am used to the D800 features and menu settings.