UPDATE: So, several friends have told me that the change from color to b&w was primarily a ratings consideration. This is based on their purchase and viewing of the R2 version of the film which has the entire sequence in glorious color.
So yet again import DVDs have proven my nemeses.
Well played, R2 DVDs.... Well played.
Thinking I'm well-versed in film, many callbacks from Kill Bill that nonetheless passed me right on by was the transition from full color to monochrome in the House of Blue Leaves sequence.
I recall it being reported at the time that the shift was done in to tone down the violence for the censors. More likely, this "concession" was actually a reference* to Men of the Monastery (Shao Lin Zi Di -- 1974), which also makes the shift from full color to monochrome when shit got real.
Most striking to me is how the filmmakers switch from black and white or sepia to red for the particularly gory moments involving the heroes. If anything, they underline the most wrenching moments. The transition also heightens the level of tension in the scene, making what was before a series of brawls, now something serious where any and everyone can get seriously messed up.**
What I respect about Tarantino's handling of the device is that he changed the tension from dramatic to comedic, using the the sequence to spotlight some of the more over-the-top violence between the two films. The violence here doesn't actually get real until it gets real, returning to the normal palette, with the Bride's victims laid out before her with limbs severed or gushing.
*I'm pretty certain this reference has been cited elsewhere by those with a more scholarly bent, but having not read their works, it's refreshing to me to meet these antecedents to work I admire on my own.
**For real, the guy at the end with the kick and the sword, and how it all goes wrong... yikes.