Frankly, I don't know whether his appointment indicates there's something there. I think more likely his appointment means that as a former prosecutor, with prosecutor's instincts, who's been involved with this fiasco since the beginning, that he is fed up with the stonewalling and deception. He wants to find out
if there is anything there, because it sure as hell looks like there is, but nobody has had the stones to start subpoenaing witnesses and putting them on the spot. The fact that Hillary was able to get away with throwing her little hissy fit is a disgrace. She needs to be put under oath, and if she tries that stunt again she needs to be challenged directly.
It's just a shame we don't have anyone else of his caliber to run a select committee to investigate the IRS, because very clearly there is evidence that that department was used for political purposes in clear violation of the law.