For me personally, it would entail living in a luxury home located in a neighborhood occupied mostly by upper middle class people (i.e., professionals, executives, etc.) preferably in a gated community, driving a luxury car that can be updated every 5 yrs or so, sending my kids to private school, taking vacations occasionally, belonging to a good gym, having household help, not worrying about food prices or healthcare costs, and having a fair amount of discretionary funds. Most of all, being able to help family and friends financially, not worrying about outliving my money, and having enough to leave an inheritance to my kids that will guarantee them the same or better lifestyle as I had.
I estimate that this can be accomplished here in L.A. by spending approx. $20-25k/mo after-tax.