What does teh Apple text in the "about this update" say it fixes? It claims to fix issues with accessing your device from the lock screen. If it fixes that or anything else I can't say, because I tried the access methods before I applied the fix and couldn't get any access to my device, and I still can't afterwards either.
I have applied the update and haven't seen that anything which worked before doesn't work now.
Have you gone to Settings>General>Software Update and and read what is posted there? Have you clicked on the link to find out what Security changes have been made?
Everything that you need to know about what is contained in the update is right there.
P.S., I have updated to 7.0.2, and it is working the same as it was. With a totally overhauled iOS, and the inherent problems that come with that type of release, it is prudent to keep up with the updates as they come out. They are coming out to fix problems that are being reported, so not sure how it can be nothing but better....