As you saw in the video, when you hail it with "Magellan!" it gives you a limited set of options, such as "Nearest Coffee," "Go Home" and "Where Am I?" If you are already in the middle of a route, the options are more limited, but useful. The two most important voice commands are "Cancel Route," which is great whenever you get to a familiar road and want to shut the damn thing up, and "Nearest Gas," which totally saved my ass just today.
In any case, you cannot speak an address; you still have to type those in. You can pick nearby restaurants, even by food type, but you can't use the same option to verbally request a grocery store or a park.
I love voice command on my cellphone, but just like that speaker-independent voice recognition, the Magellan's has its quirks. Most annoyingly, it will butt in on your conversations. Utter anything that remotely sounds like "Magellan" (we think "gel" is what it really listens for) and it will think it's being prompted. It even speaks up when radio announcers and backseat drivers are chattering away.
The Magellan Maestro 4050 also comes with traffic awareness, but like most systems, I haven't found it to be terrifically useful just yet. The radio to receive traffic data is there, but the fresh data is still missing. Not Magellan's fault, but not yet a selling point.
Voice command and the traffic kit differentiate the 4050 from the Maestro 4040. Are they worth a $200 premium? It's hard to say. I like Magellan's new Maestro systems for sure, but others will soon have voice recognition, and only then will we know if Magellan's is better or worse. Just yesterday, TomTom's US president told me that they too were working on voice recognition, and one that would recognize street names and more. Et tu Garmin?
Product Page [Magellan]