-- The 2007 Bay Area Rhythm Exchange: Stepology (which we can only hope is very much like "Vibeology") presents tap stars Channing Cook-Holmes (Riverdance, Gangs of New York, Bojangles), John Kloss (Tap Heat), Deborah Mitchell (The Cotton Club, Black and Blue), Dormeshia Sumbry-Edwards (Bring in 'da Noise, Bring in 'da Funk, Bamboozled), Sam Weber (Mr. Rogers’ Neighborhood). 8 p.m., Herbst Theatre (SF War Memorial and Performing Arts Center), 401 Van Ness; $19-$22. -- Chrome:......