I guess a Lakers fan's optimism would rely on whether or not they believe that Mike D'Antoni is a better head coach than Bernie Bickerstaff. If we look this good with Bernie, I have all the confidence in the world that we will look even better with a bonafide offensive GENUIS coaching us going forward.
Our defense will take care of itself. All Bernie has been doing is telling our guys to crash the boards and limit the other team's offensive rebounds. That philosophy can be applied to ANY team's defense, even a Mike D'Antoni team. As long as Mike is willing to let bench players like Meeks, Jamison, Hill, Blake, Morris, Ebanks, Clark (who should look good in an up-tempo offense like Mike's) and maybe even Sacre and DJO get comfortable on the floor, then we can save the wear and tear on Nash, Kobe, Gasol and MWP and have them ready and refreshed for the playoffs.
I am very eager to see how players like Morris and Johnson-Odom develop in an up-tempo offense. DJO might be able to be the guy to take the reigns from Nash in a few years. Earl Clark should become more of a weapon in this offense, mainly because he is effective as an athlete crashing to the basket. He will give us a very mobile option at the 4 with Dwight at the 5,and probably Ebanks and Nash with Kobe or Meeks as our smaller, more athletic unit. Pau can be interchangeable with Dwight, and Metta and Hill, even Jamison, can swap out as the Amare' type 4.
I am very excited. Phil Jackson is a great coach. He was the better choice IF he was fully recharged and totally opted in. Given the unknowns about how much great coaching Phil has left in him, D'Antoni might turn out to be the more prudent choice going forward. Nonetheless, I am VERY EAGER to watch this season unfold.

Nash + Howard + Bryant + Artest + Gasol + Jamison + Meeks - Hill - Clark = 33-31? In Playoff race but lots of work left to save season, Lakers could be biggest sports bust of all time. Phil IS NOT walking through that door! D'Antoni still won't play more than 8. Dwight Howard's FT% sinking fast. Kobe's working too hard. Pau cap trade? Clark 2 Expensive 2 keep? MWP amnesty? Projected '12-'13 Record 43-39. Most...Disappointing...Ever!