So, I have over 9 hours into
Fallout: New Vegas. So far, I'm quite liking and digging this. So, yes - it's basically MORE Fallout 3; feeling like a big-as-sin FO3 Expansion. No, that's absolutely NOT a bad thing - since there's a fair amount of improvements here since FO3.
The writing, prose, dialogue, and voice-acting in New Vegas is excellent - and for the most part is much better than Fallout 3. When it comes to storytelling and weaving a narrative, Obsidian and Bioware are top notch, if you ask me. While New Vegas might not tug at the emotions as much as Fallout 3 did (think The Quest For Dad stuff), the story here seems much colder, darker, and better-written.
A lot of the new features are most definitely worthwhile. Looking down the iron sights gives it a much better shooter-feel; weapon, item, and ammo crafting has been extremely useful, as I've often ran low on ammo and then was able to make some w/ a lot of the junk I've rummaged and found); and weapon modding; the Mojave Express as your way to share your Inventory b/t Towns - they all are much needed improvements since the last game.
Some things just didn't get improved at all since FO3. I still wish the Inventory system was revamped a bit - namely w/ more categories you can break items and weapons into. It'd just make it a lot easier to navigate. The graphics don't seem too much better in the technical department since FO3, either.
I haven't yet hit any bugs, but give me time - maybe I will, since this is an Obsidian game, after-all.
I haven't hit and performance issues or anything of that nature here, either....yet. On 1024x768, most stuff on my aging rig is running on Medium to High.