Yes! The Pots value is selected to work with the value of capacitor used to determine the roll-off frequency of the tone control. It's also selected with a vlue that won't load the output of your pickups too much! A lower value pot could actually decrease the signal level from your pickup.
Moving on.....
Quote by derekwalden_-33
I know that 250 is standard in a P bass yada yada yada, but Im thinking about a 100k. Can you think of any negs?

the post above mine makes little sense to me...

Right, Is it for a tone or a volume? I'd keep the same value for the volume, but if you are thinking of tone pots then: lower values filter off more treble when you turn the pot down. Higher values filter off less. If you want to lose some treble then go for it (or try a 1meg for more brightness). But if you like the current sound then don't bother changing it...
There will be a change even with the pot completely open. 100k will most likely sound muddy, it'll be quite bassy. Lower value means more resistance, and as KenG said, it will lower your signal.
Main gear
Shine ST420F
Epiphone 1966 Limited Edition G-400
Martin DX1K
1976 Silverface Champ
Egnater Tweaker 112 combo
You can try experimenting with different capacitor values as well!
Moving on.....