1+2 are great, but they are a totally different genre from what the OP was talking about.
I didn't try to imply that Fallout 3 was bad, it's quite fun actually. But it's a fact that Bethesda can't make combat that is good. New Vegas is in my Backlog, Obsidian and Before Black Isle are probably the better Developers then Bethesda in house.
New Vegas also brings a few other elements into play that make it a much better game IMO. It brings back traits, especially fun is the 'Wild Wasteland' trait. It brings hardcore mode, which most Fallout gamers prefer. It brings back some cool attributes like 'survival' and 'doctor.' It brings the iron sights, which is a huge improvement in combat. It brings back the NCR, Marcus, Tabitha and various other old school characters. It brings CEASARS FREAKIN LEGION! It just feels like a classic Fallout experience.
Seriously, get that ish off of backlog and play it. especially if youre a fan of the story of the first 2 and the gameplay of 3.
and yes, both are western RPG's, but one is a turn based RPG and the other is an ARPG.