Always a fascination of mine, for some reason. There's never been a World Cup without at least one team making their debut, and there's usually more than that. Already have on for 2006 - Ukraine. Africa could almost provide only debutantes though! With one game left in the groups, Togo have to beat Congo to qualify, Ghana need only a draw against the Cape Verde Islands and Angola have a small chance of ousting Nigeria (currently level on points, but they're playing Rwanda while Nigeria play Zimbabwe). The backwards Irish flag - Ivory Coast - lost out in the final minutes to Cameroon after Drogba equalised twice and they now look like missing out, although they play Sudan while Cameroon have a tough tie against Egypt.
Guatemala are currently fourth in CONCACAF, level on points with Trinidad an Tobago; T&T won 3-2 during the week after two late goals from Stern John. The fourth-placed team will play either Uzbekistan or Bahrain (1-0 at the moment with the second leg to come), so another new team guaranteed there. Venezuela's chances of qualifying - the only South American team never to qualify (outside of Guyana et al, who are in CONCACAF) are slim at this stage. And the Solomon Islands are still in there - all they need to do is overturn a 7-0 deficit against Australia and beat Uruguay! :p
So two new nations guaranteed and another two at least likely. Looks like an interesting World Cup from that point of view anyway.