My character is PL17/Conj16, as I see it only conjurer skill xp is in the yellow. I'm guessing that skill xp is starting to diminish slightly. I had concerns about fatigue system during closed beta but with how xp and skill points are being racked up. I believe surplus/fatigue is non-issue for me.
Note: I also have been leveling the other caster class to gain additional spells.
Phoenix Server, Final Fantasy XI (Retired)
Etoh 75 Warrior, 75 White Mage, 75 Black Mage, 75 Summoner
37 Ninja, 37 Red Mage, 37 Samurai, 37 Thief, 37 Monk, 37 Blue Mage, 37 Dark Knight
Volkmar Server, Warhammer: Age of Reckoning (Retired)
Diabolos Nox R40/RR80 Sorcerer
Greasuss R40/RR68 Choppa
Rhra R40/RR63 Zealot