One of the main problems I've got with Safari on the iPhone is the lack of tabs. On the iPhone, we are forced to hit the icon on bottom right of the screen in order to swipe through all the open windows. It's not a bad implementation. Works fine but I think there are better ways to make it work. And as far as tabs are concerned, I think most apps should implement tabs.
The few seconds saved by using tabs is not going to make or break a deal or affect workflow but the option is just something I think a lot of mobile users will appreciate.
Just as we are able to hit the top of the screen to bring down the address and search bar, maybe instead of tabs, we can directly see what web windows are opened as represented by the titles of the windows. Wouldn't that save some time?
I hope this is where the jailbreak community and the open system that is Android can have their role in all this.
Note: Speaking of jailbreaking, where are the alternative web browsers for the iPhone?