In Scaramucci, Wall Street finds an important White House ally

"The fact is that the appointment to a lot of us is sort of puzzling," said Michael Cohn, chief investment strategist at Atlantis Asset Management, a boutique advisory and money management firm in New York. Cohn also has attended SALT on multiple occasions and has interacted with Scaramucci. "He's a very smart guy -- intelligent, articulate per se. Maybe that'll play well."

On a sector level, analysts already are expecting Scaramucci to provide help to the banking sector, particularly at the top of the bracket. Jaret Seiberg at Cowen Washington Research Group expects that, among other things, the move will make it less of a possibility that a new version of the Glass-Steagall Act that separated commercial and investment banks will become a reality.

However, Seiberg cautions that Scaramucci will struggle to control a president who badly needs to focus on pushing through tax reform, infrastructure spending and raising the debt ceiling but instead seems preoccupied with battling his enemies on social media.