actually the history is off a bit. Verizon phones had hotspot at launch with iOS 4.2.6. 4.3 was released about a month later and gave the AT&T iPhone hotspot, plus a few other enhancements that were not in the Verizon phoneme at the time. All point releases since that point were bug fixes & security updates. 4.3.5 and 4.2.10 are thus not identical but for the radio.
Originally Posted by tkane2712
So while text tones were not one of the advertised changes in 4.3, it wouldn't surprise me if there was a difference.