I was thinking the same. Lol. Does seem louder and the whole OS seems more responsive. My surface was acting not so right before. Internet Explorer would crash a lot.
Unless there are random effects or machines, you are describing a classic placebo effect. One of the updates does address problems some people had with playing music while in connected standby (a problem I had not encountered) but my tablet is definitely not any louder. As far as performance goes, it should actually probably should be a bit worse at first. A couple of the patches are installed on subsequent boots so not everything is installed the first time around. Mine also just ran a cleanup function on reboot, a full day after installation. There are a couple performance enhancements in the mix but like all Microsoft OSs, the effect is never immediate. Caches, SuperFetch, etc., need to repopulate and adapt/adjust before there can be any improvement.