Now, the refresh button appears inside the address bar, and it is smaller than before. Whether or not it will be any more or less usable is unknown at the moment.
Even though the magnifying glass has been deleted (which is a cryptic symbol, if you ask me), Safari now has a Google Search bar next to the address bar, just as in the desktop version of Safari. This way you can enter search text right at the top of the browser without having to open the separate search bar.
Since 2.2 is a major point update, and not a minor one (e.g., 2.1.1), we should expect new features to be added to the iPhone and not just bug fixes. Speculation is rampant that the iPhone will add cut-and-paste functionality at some point, but Apple has given no indication that it will ever provide that feature.
As developers sink their teeth into the firmware update, we're likely to hear about a few more unearthed gems.