Many thanks to @MCMLXVI who has tweeted that Keanu was at the film festival tonight. She is located in San Franciso as was Jin Redmond who shared a selfie with Keanu earlier today.
The San Francisco International Film Festival is currently underway. Deep Web screened on Monday, May 4 at 9 pm PT. Alex Winter was present to introduce the film and hold a Q&A afterwards. @CL7676 has tweeted a photo from the Q&A and Keanu was not part of the panel. However, he MAY have been in the audience for the screening.
Update: South Indian restaurant, DOSA has tweeted that Keanu was in the house.
Update X2: Many thanks to @SamanthaJaneS who has confirmed that Keanu was at the screening of Deep Web. She tweeted that it was fantastic to meet Alex Winter, Cindy Cohn and Keanu Reeves tonight. Keanu was at the Deep Web screening.