Lil Wayne back on top. . .

Despite a 25% drop in sales, Lil Wayne’s “Tha Carter III” returns to the top of The Billboard 200 this week. The Cash Money/Universal album moved 156,000 copies in the United States, according to Nielsen SoundScan, and has now sold 1.68 million in four weeks of release.

Coldplay’s “Viva La Vida or Death and All His Friends” (Capitol) — which crowned the chart for the last two weeks — drops down to No. 2, with 149,000 and a 40% decrease in sales. The Jonas Brothers-led soundtrack to Disney’s “Camp Rock” stays at No. 3 for a third week straight with 116,000 (-32%).

G-Unit’s sophomore set, “T.O.S. (Terminate on Sight)” (G-Unit/Interscope) debuts at No. 4 with 102,000. The crew’s 2003’s debut album, “Beg For Mercy,” started at No. 1 with 377,000.

John Mayer’s “Where the Light Is: John Mayer Live in Los Angeles” debuts this week at No. 5 with 75,000. It’s the third live offering from the songwriter, on the heels of 2005’s “Try! Live in Concert” and 2003’s “Any Given Thursday.” The former debuted and peaked at No. 34 with 50,000, while “Thursday” debuted at No. 17 with 64,000.