Nadal surely closing in on Number 1 spot now. Beating the world no.1 in two consecutive Grand Slams, what the hell does he have to do?
Tennis rankings work like this: you defend the points you won last season. Since Federer still managed to reach the French final (which he did last year as well) and there's just a bit difference to him being a finalist this year (so he'll lose a couple of hundred points, nadal will gain a couple of hundred since he's gone one further than his result from last year). Federer's lost points from the aussie open (lkast year winner, this year semi), but Nadal's not done amazingly well (although he's gotten closer) during the start of this season.
What Nadal has done now, is defending his shitloads of points (equalled or bested all his result on clay from last year, gone one better at wimbledon this year and gaining points at queens) and actually improving... while Federer has gone a bit backwards. There will not be a massive difference in points gain/loss, since both are getting to finals etc.
Federer now has to defend his US Open crown and all the hard court tournaments he's won around this time last year, whilst Nadal hasn't done that well last year... this is the time for him to be gaining points, no matter what Federer does, if he does well in the hardcourt season Nadal will be no.1.
The championship race (this one is not the true overall rankings, but the ranking that gets reset every year, to show who's actually leading the race to finish the year as no. 1...) is being led by Nadal, which shows he's now in pole position to finish as no. 1 in the overall rankings.