Around 5,000 people attended Friday's concert and many then marched down the capital's main avenue to the parliament building.
Since January 20, the singer mentioned in the AP story, Giorgi Gachechiladze, who's also a poet and political satirist, has locked himself up and said he won't come out until Saakashvili resigns (except to do concerts).
In a curious mix of hunger strike, nighttime cable TV, and Big Brother, Gachechiladze's incarceration is the centerpiece of a popular TV show.
He told Reuters in February that, "Whatever happens, whether dead or alive, I'll emerge from here a winner."
-- Luke Allnutt