It is debatable.
If you can get some outland green boe's and level smoothly through Azeroth content go for it. Takes a little longer but in the end it makes you a couple hundred gold if you save some of the SMV/Netherstorm quests for after you ding 70 (for some people makes them a couple thousand gold). Course now with 25 daily quests that is a non issue.
58-60 in Outlands goes by exponentially faster than it will in Azeroth, as in you will ding in 2-3 hours or less. Also as mentioned with the dailies for gold, saving quests for 70 and starting outlands late doesn't make as much sense anymore.
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Bode - 100 Holy Paladin - Lightbringer