The legal process is:
Threaten him with contempt (done) which is required step prior to filing with the court for the contempt order to show cause, and if Rove looses, which he may as there is now evidence and testimony which is persuasive, the court will rule he must appear or be in contempt.

If Rove fails to appear, then he IS IN CONTEMPT.
Next, the order is taken to the federal marshals, who locate and arrest Rove and bring him to the federal jail or hopefully to the jail beneath the house chambers, which they have a right to do It makes me laugh to think he'd be right under their noses

.

Liklihood of Success: 70% - I am inclined to believe this will go far with the election being close, and Bush being lame "d" (I know he was all along) but powerless, AND evidence and testimony in hand he will have to sit and answer questions.
If he does not answer questions and invokes executive privilege, off to court they go.

Potential outcome: Barack will be President... and the legal process may be slow, but it will become inevitable at some point that Rove will have to talk or be jailed.  

At some point a lawsuit will be filed, (civil) and he will have to answer for the crimes he committed against Dan Siegleman and the female attorney(forgot her name) whose house was burned down after she gave testimony corroborating Karl Rove's involvement in the telephone conference to "get Siegleman".