The only full-size LCDs (that is, not in cellphones, MP3 players, or PDAs) to use LED backlighting is the $5000 Eizo CG220 22" calibrated graphics display and the $15,000 Sony Qualia 005 46" HDTV. (A few other companies have announced LED-backlit displays, but they haven't hit the streets yet.)
So the MBP is definitely fluorescent.
tooki