The Fallout community has been aware of that (fake sites, TS2299, etc.) for weeks, jussayin'. Still, we all know Fallout 4 is coming; Bethesda didn't fight that expensive legal battle for nothing and a few of the voice actors hinted at it a while ago.
Although if we had vehicles the game would have to be a little more demanding. In F:NV, The Strip is split up by gates as it is, and was seen without gates in an E3 2010 demo so the gates were obviously technical limitations rather than design choice. Having to stop and go through a loading screen every corner would be pointless.
Hopefully with next-gen, Fallout gets a complete overhaul. New engine, no more separated maps, and vehicles.
Of course, if they wanted planes, a good idea for the edge of the map would be not to have invisible barriers, but to have a huge empty desert or something around it, and going too far out would give you a sh*tload of rads and kill you.
The Strip/Freeside being cut up was a bit disappointing, but if you play on PC there are mods that join them together as originally intended by Obsidian. But yeah, console limitations are also why the Hoover Dam battle was so...well, crappy.
Speaking of overhauls, I hope Bethesda doesn't go crazy with making NPCs 'essential' again. They sort of overdid it in Fallout 3 and Skyrim.
In New Vegas you could go off the map, and there was desert/mountains/enemies for a while until it just turned into a flat, lifeless void. As far as planes or Vertibirds, I guess it'd depend on where the next game takes place. It'd make sense for the Enclave/BOS to have Vertibirds (though to be honest I think those factions are overused, though seeing the Enclave Remnants was kind of fun), but I don't want to see raiders having them or something silly like that. ;D