I really can't believe any of you are using NV to try to point out how non-linearity should be done. NV felt far more linear to me than any of Bethesda's games. Every playthrough resulted in the exact pattern of quests which anyone who's played the game is familiar with. It funnels you along the exact same route. Yes there are choices to make and it does have an effect on the outcome of the game but it doesn't really change the course of how you play. NV even has a conclusion that ends the game permenantly. Yea you can artificially hold off on it but that's your choice not what the developers wanted. They hold your hand to almost every single location in the game. It's a thinly veiled trail of breadcrumbs that you follow from start to finish so that you end up seeing every location at least once. There isn't even a need to go exploring because the story takes you everywhere if you just follow it.
NV also has no random events at all, very few enemies in the wild making exploring very uneventful other than key locations, the land mass is extremely small compared to any of the Bethesda games, there are invisible walls everywhere (if that's your thing more power to you but open world games should be open in my book, you may not be able to climb every part of the mountain going up but I take shortcuts all the time coming down. You can't do that in NV due to invisible walls), and NV had very little underground area and most of what was there was cookie cutter. My point is that NV had it's own issues and limitations. There were just as many complaints about those issues on the NV forum when that game was in it's prime. It wasn't any more of a holy grail for RPG than Skyrim is so stop acting like it was so perfect because it wasn't.
It certainly had invisible walls people complained a lot about and it certainly pushed the player in a certain direction - this was pretty easily bypassed with experience of the game. That was a game design decision you either like or don't but makes sense as new players got an introduction to the world and what was going on, on your second playthrough you'd know enough to bypass all that if you wanted. It also had a hard ending which is really the only way to have multiple endings with massive consequences for the gameworld - it didn't end until the player decided they wanted it to end, so I personally never saw what the fuss was about - give me multiple interesting endings over F3's lame ending (made ultra lame by Broken Steel) just so you don't have to save the one final battle until you're finished any day. Beth wouldn't even let you join the Enclave when trhey still had a hard ending - just like you can only do one tiny sidequest for the Thalmor in Skyrim. New Vegas never forced you into quests or had NPCs harassing you into undertaking them like Skyrim does - hell, you could just wander round kiilling everyone you saw if you felt like it and breaking most of the quests - it supported that too.
The gameworld did get a bit empty in places and that was a flaw, but on the other hand random encounters just get repetitive as you see the same ones over and over. Why Skyrim couldn't have had regular travellers who are just travelling between cities and nothing more spawning on the roads I don't know. That would make the themed random encounters mean something more and spread them out so they didn't get so old so fast.
The MQ did not show you much of the world. In fact, there was loads of content that wasn't at all obvious - the companion quests tended to have very specific triggers you could easily miss. What it did that Skyrim doesn't was support pretty much whatever character you fancied - you could join most factions in the game, all of whom had intelligible motivations. And people noticed what you did and reacted to it. It's real strength was the way the quests made a bunch of interlocking stories that felt like a real narrative and made you an important player without being King Of The World and being in charge of everything (though nobody of course notices you are in Skyrim). The storytelling actually made sense and had a level of complexity Bethesda seem incapable of managing - not forgetting NV was made in what? 18 months or something, was on a waaaaaay tighter schedule and had a lot cut from it due to that - and it still managed to tell a bigger story with far more decision making and consequences than Skyrim manages.
Bethesda seem to be moving into thinking if they give you a big world and a bunch of stuff to do, it doesn't really matter what that stuff is. They make huge roleplaying games, but aren't putting thought into supporting roleplaying. If Bethesda had made New Vegas, you'd be forced to support the NCR and you'd be able to - indeed pushed towards - become chief of every minor faction along the way - that's the Skyrim model. The civil war was a step in the right direction, but it's very badly done. ~They seem to think they have to aim their games at teenage boys who only care about being being the biggest, baddest boss of fantasyland (that's not intended to be ageist, I'm speaking in terms of commercial stereotypes). They're kind of like a band who's got to big and care less about the music than what's going to sell the most records. Unfortunately, that kind of strategy can backfire in the long term.