Eminem [ tickets ]’s “The Marshall Mathers LP” has hung on to the No. 1 spot on Billboard’s Top 200 album chart for the fourth consecutive week with sales of roughly 519,734 units in its fourth week of release. Eminem is currently appearing on the Up In Smoke tour, which kicked off last Thursday (6/15) and features fellow rappers Dr. Dre and Snoop Dogg.

Britney Spears [ tickets ]’ “Oops! … I Did It Again” kept its No. 2 position for the second week in a row. The album debuted at No. 1 last month, and sold roughly 1.3 million copies in its first week of release. Spears launched the summer leg of her North American tour in support of “Oops!” on Tuesday night (6/20) in Columbia, M.D.

Debuting at No. 3 this week is “Riding with the King,” a collaboration between guitar greats Eric Clapton [ tickets ] and B.B. King [ tickets ]. The disc features cover versions of 12 classic blues songs, including the title track and “Hold On I’m Coming.”

Kid Rock [ tickets ]’s compilation disc “The History of Rock” was pushed down to No. 4 this week, while ‘N Sync’s “No Strings Attached” managed to stay in the Top 5 for the twelfth consecutive week. Rock heads out on the Summer Sanitarium tour with Metallica, Korn and others next month, followed by a late-summer headlining tour of his own. ‘N Sync, meanwhile, is in the middle of a North American tour that wraps up next month with four shows at New York City’s Madison Square Garden.