CalArts will present a city-wide celebration of composer Iannis Xenakis beginning in November and lasting through February. A highlight of the proceedings will be an open-air performance of his opera “Oresteia,” and it’s free. … Pianist and blogger Jeremy Denk writes a thoroughly crabby and erudite manifesto on program notes. … Dean Corey, president of the Philharmonic Society of Orange County, has started a blog and he seems to have hit the ground running. … The New York Times announces that Orange County, due to changes in demographics that are transforming the area, is no longer Nixon Country. “You have areas of poverty and areas of great affluence and less of a middle,” says one source. Arts organizations and newspapers take note. … The LA Phil has unveiled plans for Gustavo Dudamel’s second season-opening gala. Juan Diego Florez will sings arias by Rossini, but the fun may be in the instrumentals, which will include the Overtures to “La gazza ladra” and “William Tell” and Arturo Marquez’s Danzon No. 2. … Carl St.Clair will conduct the Pacific Symphony’s opening night concert after all.