Although the ability to use your phones as a portable wireless router, sharing your 3G connection with your laptop, is a feature normally reserved for Android 2.3, it's present here thanks to Motorola's own app. Orange, currently the exclusive network provider for the Atrix, blocks this from working though unless you pay an extra tethering fee on top of your existing monthly fee.
The Exchange-compatible email and calendar apps can accept and reject Exchange meeting invitations. The Contacts app can not only pull information from Exchange Global Address Lists, but also information from social networks such as Facebook and LinkedIn. It's fairly sensible about merging information from different networks together it thinks are about the same person, but you can always change it if it gets it wrong.
We had some trouble getting the Motoportal web interface working over WiFi, but it worked without a hitch over USB
As an alternative to using Windows Explorer to manage the files and media on the Atrix, you could instead use the web interface. It's accessible from any web browser and, unlike previous Motorola Android phones, works whether the Atrix is connected to your computer using a USB cable or is merely on the same WiFi network. It isn't as sophisticated as iTunes, but it works well enough for quickly transferring documents and photos.
If you need to get some serious work done, a lite version of the Quickoffice app is preinstalled on the Atrix. This Microsoft Office-compatible suite can only open PowerPoint presentations, not edit or create them, but it can create and edit Word and Excel files although it lacks the formatting options and formulae options found in the full version. It's still good enough for reading or light editing and it can open PDFs too.