Will they notice?

The people who care will be the ones that notice. However, the ones that don't will be the ones to tease you about it, after someone else points it out. Some people might even try to figure out what changed, so let them try and see what kind of ideas they come up with. When I shave my beard, I always have fun listening to what people come up with about what I have changed. It makes it fun, rather than offensive.

It probably depends how drastic of a change you made and if you look better than you did. Then, yes, I think people would notice if it's a big change & it makes you look better. If you just look different, they will probably notice too, but you probably won't get as many compliments as you would if you are dressing better & looking better. Just my thoughts.