As an earlier poster said: It would be almost impossible to actually test the same bass with different fingerboards and keep all other elements the same. So this argument is not getting resolved anytime in the next few decades.
A few days ago I had the chance to pluck on five or six J's and Super J's as well as my G&L, all unpluged. Here's what I heard:
My G&L: Maple on Ash - Nice high-mid snap. Balanced sound.
My new 60's Jazz: Rosewood on Alder - MUCH brighter than my G&L when they both sport new XLs. Actually the Jazz's are a bit more broken in.
Mike Lull 4 string J: Maple on Ash? DARK. I mean Thumb Bass with old steels dark. Nice mellow sound, but definitely not the stereotypical "maple" snap.
Sadowsky Metro 4 string- Maple on Alder (I've been corrected, this must have been Ash) - Sweetly balanced. Blindfolded I would have said Rosewood.
Modulus VJ4 - Graphite - Sizzling highs and gut kick bottom (unplugged!) Certainly FELT different than the wood necks (whether my finger pads touched the fingerboard or not!)
You get the point. No pattern based on fingerboard alone.
Can we all agree that the sound YOU get out of WHATEVER bass I put in you hands comes mainly from (and roughly in this order):
1) Your playing technique (Imagine that!)
2) What pickups are on the bass AND which setting you are using
3) What strings you use.
4) Your amp system or recording signal chain.
5) The beautiful or gnarly resonant qualities of the main body and neck woods on your instrument. This is where the subtleties of you tone are found. This is why we buy nice basses, but if you are any good you can play the hell out of a $300 bass with decent pickups through your rig.
6) Finally, the fingerboard. Which cannot be separated from the other materials mentioned in number 4 above and is therefore disqualified from the individual events!
I will grant you this: The fingerboard definitely affects how you feel ABOUT your bass! (awwwww, so sweet) Seriously, it has more to to with your response to the "vibe" of the instrument and its looks than the actual sound. It matters...but only to the player...and you can't hear it on a record.