I'm picking Ferrer over Tsonga in the semis.
I'm not basing this on H2H or who is most rested or each players' history. An argument can be made that they are a complete wash on all 3 of those categories. My argument goes thusly...
The key to Tsonga's win over Fed today is that Roger gives Tsonga a target because he's an aggressive player. Against Ferrer, the quintessential defensive player, Tsonga has no chance to hit past like he could today. Likewise, Tsonga is the aggressive player. Ferrer will have a field day hitting versus a target. In this way, he will frustrates Jo then watch Jo quit before the end of the second set.
EDIT: I'd be remiss not to add that, because Ferrer will have time to pick targets, he, unlike Fed today, will get to Tsonga's weak wing, his very average BH.
What you say?