As it stands:
2 Murray 8660
3 Federer 7760
4 Ferrer 6830
5 Nadal 6075
And of course Murray could pick up more points yet.
Nadal could return to #4 if (when) he wins Madrid, if Ferrer loses to Haas today.
If I'm not wrong, Murray is guaranteed top 2 seeding for French Open now. Federer can only reach 8400 points (if he wins Rome), Murray will have a minimum of 8480 (if he didn't play Rome) or 8490 (first match exit). Ferrer maximum is 8380 (he'd have to win Madrid and Rome.. let's be honest, that's not happening) and Nadal's is 6895 if he wins both titles.
Live rankings for those among us who aren't fussed with the mathematics and just want to see it in simple form http://live-tennis.eu/