Yes, the OP is correct. It happened the instant I updated any device to iOS 8 and hasn't really improved since then.
Since others are apparently missing it, here are the main symptoms:
- Previously Facebook would open by showing you the last thing you were looking at. You could stare at that until more content loaded above it. Now it just shows you a white page until everything is loaded. This usually means you're staring at nothing for the first 6-8 seconds after you open the app. This started with iOS 8.
- Since getting iOS 8 I would say I've had about this many total phone freezes:
On Springboard: 2
In all other apps: 6
In Facebook: 20
There are, of course, other minor things that are wrong with Facebook, but they were the same in iOS 7 so I won't bother mentioning them here. Those are the two big ones that started after the OS update.