I totally disagree, note the 80's Lakers with Kareem.
While Kareem was a fitness maniac who did yoga, tai chi, etc. and still had that unguardable sky hook well into his 40s, WOW's comparison is remains valid. Shaq can still rebound and it'll be about getting the ball out to Nash for the break, as fast as possible. The Suns aren't short on gazelles--Amare, Bell, Barbosa, and even Diaw can run. Shaq isn't in as good a shape but he's still a big body and a physical presence to account for. I think that people forget too soon how effective Shaq has looked when surrounded with prolific three point shooters (Damon Jones, Jason Kapono, James Posey, all who Miami just let walk).
As it is, the Suns just traded their BEST player!!!
Randy, you're giving too much credit to Shawn Marion. He's not the Suns best player, that's Steve Nash. I'm not about to take away from Marion, a guy who for the better part of his career has been underrated, but let's not over-represent what he brings to the table.
Marion is a versatile defender but has absolutely NO shot at defending true big men like ones the Suns will face in the playoffs. Gasol, Ming, Boozer, Odom, Duncan, and maybe even David West will destroy Shawn Marion in the post. He's too undersized to handle their post game when they go deep. You can put Marion on a guy like Nowitzki who plays more of a perimeter face up/high post game from 15 feet, but none of the other elite PFs. Odom has absolutely DESTROYED Marion in both of the last playoff series. I also believe that, while fashionable, calling Phoenix a dreadful defensive team is no longer accurate. They are in the upper 3rd in opposing team FG% and 2 best team in FG% differential, 4th best in opposing team 3P%, and 6th best in opposing team APG (kept out of the Top 5 by the Spurs, Rockets, Pistons, Mavericks, and Celtics). I think people focus too much on Phoenix allowing opposing teams to score 103.9 PPG (6th worst) and not enough on scoring differential of 5.9 (4th best).
Marion, although an exceptional rebounder for his 6'7 frame, has his numbers inflated by the pace of the game that the Suns employ which usually leads to greater rebounding opportunity. Miami, on the other hand, runs a slower system and therefore less possessions which means less opportunity for rebounds. Looking at the metric of rebound rate (which accounts for opportunity to get a rebound), Shaq's rebounding actually trumps Marion's.
Although Marion can score in a variety of ways, almost all of them are initiated by another player creating the opportunity for him. Someone has to drive and dish to Marion for the shot, or drive and find him diving to the basket, or shoot a shot and miss for his easy put back. You cannot just give the ball to Marion and say, "Score." Although he does occassionally run pick-n-roll with Nash, its to nowhere near the extent or success of when its Nash and Stoudemire. Very occasionally, he'll initiate and try a one-handed half jump hook which often needs precise touch because he doesn't use the backboard. Consequently in the tough, ugly, grinding basketball of the playoffs, Marion has often-times seen his scoring drop significantly. After all less of a free-flowing offense means less opportunity for Marion's teammates to find him for scoring chances. Shaq on the other hand thrives on playoff-style basketball.
Last but certainly not least, has been the effect of Marion's growing dissatisfaction on locker room morale. The book, "7 Seconds Or Less" that westkoast mentioned, I read last year, and it was vividly brought to light how Marion despite great personal and team success was despondant and abrasive much of the time. Observers have time and again stated that the Suns were joyless this year, bickering, going through the motions. Nash growing weary from coddling the endless fighting between Amare and Marion, super sensitive to any slights real or imagined. The truth of the matter was that the players and staff have long been past the point of believing they'd be a better
team without Marion.
------------
I have already said that this move smacks of desperation in the face of the Lakers stealing Gasol. Though after you take a step back and evaluate all aspects of the move--it isn't as horrible or as lopsided as most would have you believe. The Suns have definitely mortgaged the future but they know the window Nash has provided is fast closing. I think the Phoenix faithful would say reaching the ultimate goal, which has eluded the franchise its entire 40 year history, is worth the very large gamble of taking on an old Shaquille O'Neal.