I really like the new smooth animations, and I am LOVING the cached previously viewed pages.
A few things that I miss, and a few suggestions (Please, I am NOT trying to tear down this app, I LOVE it and have been a long time paid user. Take my opinions however you like):
1. (This is the most critical loss IMO) I miss the ability to hide the tabs, UNLESS there is more than one (then the tabs always appear at the top until you get back down to a single tab again). I know that the option is still supposedly there in the settings, but it doesn't work. As it is, no matter what I choose in the options, they are either always there, or always hidden. Also, if this were again made a possibility, it would make the tab selection in the bottom bar redundant.
2. The Quit option is buried deeper into the bottom bar (maybe if the tabs were in use, the tab button could be changed to a quit button?).
3. The bars appear by default when opening the browser, and then I have to make them go away. I would prefer it to be the other way around to where I would have to make them appear.
4. I miss the ability to separately access the bottom bar by hitting the menu button, and the top address bar by swiping downward.
5. The sub-level options in the bottom bar need to have labels appear when the options are highlighted/pressed/selected... then again, maybe not. I'll get used to them soon.
6. The sub-level option bar could be lowered. The height of its display seems to especially become a problem in landscape viewing
7. We could maybe use a setting to disable the opening/closing animations.
8. Clicking a tab no longer dismisses that tab (I REALLY miss this option!). Instead it gives options to either create a new tab or dismiss the current tab... I prefer the old format where clicking a tab would dismiss it, and clicking the '+' tab would create a new tab.
9. Clicking the address does not allow access to the address. Instead it pops up an option to either access the address or open the page options, which is redundant because clicking the star next to the address opens the page options.
10. Pinch-Zoom opens links. Multitouch input should disable selections.
Overall, the performance increases are GREAT! But I am not a fan of the screen-intruding redundant-content popup options at the top of the screen, and the forced "all or nothing" access of the option bars in general. A GREAT start to v6 though!
Edit: And I'm not a huge fan of the new icon... not that it effects the use of the app though (and I can swap it out with bettercut).