I too am not in the habit of sitting at my computer with a stop watch, however this 18.3.2333 UI does load noticeably quicker without the requirement of a stopwatch. This was on my general test system, XP Pro SP3 Desktop
That said, I did break out my stopwatch, used on my morning exercise:
I did a test on loading the existing UI with all of the normal programs I would have loaded/running before update, that took 6.03 seconds.
I then completed the update including the update and once things had settled down ran the test again, this took 3.64 seconds. This was with negligible programs running (startups only) so no additional load.
Now I loaded those programs I use regularly and started the UI again, no difference really loaded in 3.59 seconds. I may have been a little quicker on the buttons this time as the first ones caught me out a little.