Cheat Code Central offers a hands-on preview of Fallout: New Vegas, based on a short demo they played at the latest PAX.
While I didn't get to see much of this for myself during my relatively brief time with New Vegas, I can tell you that fans of Fallout 3 will feel right at home. Everything from the wasteland itself to the NPCs to the look and feel of your Pipboy is largely the same as in last Fallout entry, making gameplay easy to pick up and play if you've spent anytime roaming around the Capitol wasteland. My time in New Vegas was then spent talking to random folk about their various problems, the most notable being an interaction with an NPC who was looking for a shady character that had apparently involved himself in some disreputable behavior in the town of Goodsprings. I was able to find him hiding out in a seemingly abandoned gas station. Although the man was at first suspicious of my motives in finding him, he quickly dropped his guard.