Let me tell you..
Fallout 3, This may not be involved with what you are saying, But this is what I feel, Fallout 3 directly ripped off the story of Fallout 2, And a little from Fallout.
Let me say what exactly they ripped off.. "MUST FIND GECK AND KILL MUTANT VAT PEOPLES, THEN MUST FIGHT ENCLAVE AND SAVE THIS AREA OF TEH WORLD."
And that really made me angry about FO3 after i played FO1/2.
Talk about a crappy writing team.
Sure, when you intentionally dumb down things, no crap they sound lame and boring.
Fallout 3 had purpose. Your father worked so hard on the project, and here are the enclave trying to [censored] things up. Your father dies for his project, and if that isnt motivating enough to complete it, then what in gods name is?
New Vegas, you are a delivery boy/girl. You get jumped, and you want revenge on who did it. Sure, acceptable. But once you do that, what is your motivation to help out these different groups? Yo want to talk about NPCs comming up and saying "HEY HELP ME!", ok, let me list them for you.
House - Victor tells you house is waiting for you soon as you enter the strip.
Legion - Whats his face walks up to you and gives you the mark item, in the strip of all places.
NCR - the only main faction that doesn't actively broadcast their need for help.
Now for the minor things. It fealt like nearly every [censored] quest, NPCs wanted you to do ANOTHER quest just to get some simple information. Example. Novak. I tracked benny there. Talk to the sniper for info. He says he will tell me if I clear out repconn. Ok, I go there. Great, now I have to help out the ghouls., but before I can do thay I need to clear out the nightkin. Then I need to get travel to go get some items. God, does it ever end? In the end, in order to complete quest A, I had to do B, C, D, and E.
Now the locations, they are bad to. There is little to no connection with any of them. Goodsprings? Just a map marker. Nipton, why bother. Novak? Not much there. Jacobs town, again, not much. Even the strip has little attraction. Never once did I get the feeling like "This is where I belong." In fallout 3, I felt at home in Megaton.
Now, lets not get confused, My list of problems with Fallout 3 is long, but NV is longer. And at the same time, there are things I love about each, and things I with were mashed together. No game is perfect.