No way the upgrade would have caused the issue I am seeing? Perhaps it somewhere on my end then. I am also seeing disconnections even with 3 bars (i.e. connected but no internet so basically DCed). Happened to another one of our laptop as well. Desktop (wired) is fine.
Maybe I will try to reset the router later.
I would be surprised, unless it was something that Asus changed in the interface init code between 372 and 374.
I would recheck your router settings just in case before trying anything else. Your router might have switched to a different channel if it was previously set to Auto.
Anyway, I will be ditching that old driver in the near future, and switching to the newer SDK6 driver. That driver resolves the vast majority of reported issues.