i've noticed the same thing. Safari seems to hang and won't finish loading a page, or just loads choppy and slowly. Switching over to 4g fixes it immediately. I think it started around the time of this most recent ios update. Same thing happens at work and at home. I tried running a speed test, and it doesn't seem to be reading slower than normal, so i think it is a safari (or any browser) issue.
Anyone else?
I'm on ipad 3rd gen with most up to date ios.