I would ask you to include another option that i intend to vote for.
"- Wait for reviews"
I amongs those people that were very disapointed by Fo3 and hope they will improve the experience after FoNV.
I get that it isn't a widely shared opinion, but for me, it was really a painfull experience to play Fo3 and don't want to do that again.
If Fo4 is the same level of Fo3, or even worse, i won't play it.
On the other hand, if i read enough good reviews (from trusted sources) that will convince me that the game is significantly better than Fo3-FoBos, i might get it.
Because i want to believe they can improve themselves. From the level they come from they can only go up.