I started a Monk back during the 360 beta test, got frozen around 40 because I couldn't get my darn Okote to drop (1/23), so went to RDM, then stonewalled at 70 because Maat kept handing me my derriere. Dancer became my favorite when Wings came out (Beat Laila 1/3), but as soon as I hit DNC75, I came back home to Monk, and now my 3 favorite jobs are Dancer, Monk and Scholar.
As for Black Belt, I didn't get mine till about a year ago (Got Tongue/Beard within a month of each other, but then the LS I was on collapsed and I was stuck duoing/trioing Adamantoise for months, then lucked out when some friends gathered and we snagged Aspi.