Laundry list of the changes from the support pdf:
Here is the list of things that are included in the new update.
+ Improved Web browsing with pre-installed Adobe® Flash® Player 10.1
+ Support for 720p video recording.
+ Transfer data faster with 801.11n Wi-Fi capabilities.
+ Easily switch between the eight most recent applications.
+ Enhanced browser performance for faster loading of
+ A screen that works for you and your apps.
With Android 2.2, you can rotate your screen 270 degrees—either
to the left or to the right when moving from portrait to landscape
mode—to work with apps in more directions.
+ A new Mail Stream widget increases ease of use.
+ Text Message Widget.
The new text message widget offers fast access to your messages
from the home screen with a quick swipe. Scroll up and down
through the list of all your text conversations in one screen. Keep
the conversation going, faster.
+ Automatic app updates.
Always have the latest versions of the applications you’ve
downloaded with automatically updated Android Market™ apps.
And you can choose to store applications in your device’s memory
or on a storage card for more capacity.
+ Updated software changes provide improved security.
+ Improved battery life.
+ Manage Contacts more efficiently with updated contact details.
+ Instantly know the strength of your signal with improved
+ Connect to Visual Voicemail when Wi-Fi is enabled.
+ Easily move between Today view and Agenda view in the
+ Additional support for Backup AssistantSM PIN retrieval for new accounts.
+ Play Visual Voicemail messages through speakers when connected
to Bluetooth® car kit.
+ Keep track of music with organized Music Player application.
+ Updated People application to accommodate contacts with
+ Access Corporate Directory information on Microsoft® Exchange.
+ Save new contacts with “Save to People” option for Visual Voicemail.
+ Call a number back immediately from text messages.
+ Improved CityID application.