Fender Jazz and P bass : the difference ?

From Mr. Lasley's article, Tone Loco:

Fender makes two classic bass styles. The “Precision” (or P-bass) has two half-pickups grouped half-way between the neck and the bridge. They found the best place to put a single set of pickups. The “Jazz” bass has two pickups, one closer to the neck, and another close to the bridge. This allows you to selectively change the balance between the fundamental and the overtones. Different guitar makers connect and control the two pickups differently, but the added flexibility is what is desired. (Note: there are other differences between the P-bass and the J-bass as well)

I also imagine that the Fender website would have more info in regard to things such as scale lengths, neck radius and the like.

Peace

The J-bass has more tonal variety since it has two pickups. The neck PU is more bassy, the bridge has more of a honk sound to it, and blending the two makes a gread slap tone. They generally have slimmer necks than a P, I think.

A P-bass has less tonal variety, but its tone is classic and works well in almost any situation. So both are very versatile axes. The P-bass sounds more powerful than a jazz to my ears. More growliness and more thump.

Both are good basses, and you've really got to play them both to understand them. You can also get P-J combos that add a J-bass bridge pickup to a P-bass. That's a great option, since you get the tone of a P and the variety of a two pickup bass. I prefer the P myself. If I only had one bass, it would be a P-bass. As a matter of fact, I do have only one bass, and it is a P-bass (with added J pickup). Your mileage may vary.

EDIT: As far as scale length goes both are the same: 34 inches. I don't know about fretboard radiuses. Those may vary by year for all I know.