Opening night of David Gilmour [ tickets ]'s North American tour featured surprise guests David Crosby and Graham Nash.

During Gilmour's Tuesday (4/4) appearance at New York's Radio City Music Hall, Crosby and Nash sang harmonies during "On an Island," the title track to Gilmour's new album (they also sang back-up on the album track), as well as "The Blue," Pink Floyd's "Shine on You Crazy Diamond" and the Steven Stills song "Find the Cost of Freedom."

Rapper T.I. [ tickets ]'s "King" enters The Billboard 200 album chart at No. 1 this week, with sales of about 522,000 copies in the US.

Tim McGraw [ tickets ]'s "Greatest Hits Vol. 2--Reflected" debuts at No. 2, while the TV-movie soundtrack "High School Musical" slips one notch to No. 3.

Ghostface Killah [ tickets ]'s "Fishscale" enters the chart at No. 4, while Rob Zombie's "Educated Horses" rounds out the Top 5.

The Thursday (4/5) Gorillaz concert at New York City's Apollo Theater will be streamed live via the MSN Video website.

Following the show, highlights will be available on demand, along with other Gorillaz-related fare.