Right now it falls short in some ways but may do more in some others (but then no two apps can ever be the same).
- Exchange Contacts:
Available in the app's own contact picker, to bring it up, use the picking button(s) next to each recipient entry field (on the compose screen).
This will show your personal address book (with search) and provide access to the GAL (Global Address List, corporate directory) with search.
Contacts will not, however, sync with Android's Contacts. This may change but right now that's how it is.
- Calendar
Right now you can see invites in incoming messages, and when you reply (decline / accept), the resulting "event" will be saved on your Exchange server, and will be visible in your Exchange web mail / Outlook / etc.
This will change soon, I'm working on proper Calendar sync right now, and it's nearing completion:
Events pre-existing on the server will sync to the device's Calendar... you'll be able to create / delete / reply from Google's Calendar app and third party calendar apps... third party calendar widgets too I guess...
In other words, Aqua will *sync* your Outlook / server calendar with the Android device.