I updated my iPhone 5 but not my iPad Air. Phone lags like mad now. Seriously, the Podcasts app, it's not an exaggeration to estimate I get about 1.2 seconds per frame when I'm scrolling through my lists. You know, the ones built on the UITableView framework, engineered back in iOS 1.0 for optimal efficiency, smallest memory footprint, and readibility on small screens. It chops and lags so badly I pull my finger down, wait a few jerky updates, repeat. When I want to dowload or interact with the app, I have to hold my finger on the screen for about a full second to interact with it. Of course, with the wonder of iOS 7/8, there is no immediate feedback like an animated button depressing to let me know I had a successful input, so I have to try a few times quite often.
Fan-flipping-tastic. God, I wish I was still on 6. So, I'll update it immediately whenever they roll out anything new, because in my opinion, it really can't get any worse. Until it does.