Yes, even though spider gear is the normal term for those side gears, the reference is made to "two-pinion" and "four-pinion" differentials. (Technically a pinion is any gear that turns or is turned by another gear, I think.) Some differentials do have only two. Starting with the four-cylinder turbo models in the late 80s, Toyota began using four-pinion diffs with their more powerful engines. All the V6 models are so equipped, I believe, but there are still differences. The TRD locking differentials use a slightly smaller-diameter ring gear than the non-lockers. This is why some serious rock-crawler Toyota drivers buy standard V6 third members and install ARB lockers. (My nephew Jake, a master Toyota mechanic, says the TRD diff is plenty strong for all but the most demanding applications and highly modified motors.) The only drivers at all likely to run into trouble with Toyota third members are those who install very low gears with tiny pinions (that is, the ring-and-pinion one, not the spiders). Like, uh, Scott did on his truck.
I think the query about a "12-bolt" might be a mistake; I've never heard that reference to Toyotas either. That's a GM axle.