.........the fact that MS has also released an update blocker..............
MS issued the same/similar blocker when IE10 was introduced to Win 7 users.
...........I'm certain that there are reasons that would make it better than my current version...9, but are there any reasons that would make it worse?
I think that is your subjective opinion. I started with IE7, then 8, then 9, then 10, never had problems.
Whether you want it or not is your preference.
........... If I did install it, could it be uninstalled, if I chose to do so?
Yes. In fact if your Win 7 came with IE8, you can use the tutorial below and revert your IE back to IE8.
Same procedures applicable to uninstalling all IE versions.
** Please pay attention to the...