It's hard to tell what's going on from TI's description, but yes, the TI DAC11001B is 20-bit ladder DAC--just like the AD5791, and the DAC10011A. The DAC10011A measures pretty terribly at high frequencies; this one doesn't. The DAC10011A was not the favorite Yggdrasil flavor (understating this by a LOT). The DAC11001B trades blows with OG--while also being the best-measuring multibit DAC in history.
Here's a comparison of DAC11001A and B at 20kHz (one channel DAC11001A, one B, same unit, real time.) The difference is astounding. TI saying they "improved" the DAC11001A is like a chef saying he "elevated" a McDonald's hamburger to a Michelin-star dish. TI hit it out of the park.
In terms of traditional THD+N specs, the DAC11001B is about a -118/9dB implementation in Yggy (1k full scale sine, 20k bandwidth, all hail the mighty and true APx555, yadda yadda).
And yeah, I know, measurements aren't everything. But in this case they are no reason to be afraid.