Week of Dec. 20

Twenty five years ago this week, Julian Lennon was in the top 10 with his first hit song, "Valotte." He's back this week at No. 40 with "Lucy," a collaboration with singer-songwriter James Scott Cook. This song is a fundraiser for lupus research. From now through March 15, 2010, 100 percent of the proceeds from each download of it from iTunes will be donated to lupus research. Both artists talk of their personal connection to lupus: James’ 92-year-old grandmother, Lucy Cook, has lived with it for years, and Julian’s childhood friend (and reported inspiration for the Beatles' "Lucy in the Sky with Diamonds") Lucy Vodden recently died at age 46 after a long battle with it.

Meanwhile, the other two new songs this week are from Alicia Keys' latest album, "The Element of Freedom." Her official second single, "Try Sleeping With a Broken Heart," enters at No. 39, but it's outpaced by her album track duet with Beyonce, "Put It in a Love Song." The upbeat number, which is similar thematically though not melodically to Beyonce's "Single Ladies (Put a Ring on It)," is the highest new entry of the week at No. 33.

While most songs between positions 30 and 11 move up the chart modestly (if they move up at all), Raphael Saadiq's "Staying in Love" leapfrogs 22-10. That gives the former Tony! Toni! Tone! frontman his second Top 10 solo hit after "Never Give You Up" from late 2008.

At the top of the charts, look for an interesting chart battle over the next several weeks between three disparate female singers: Norah Jones, Susan Boyle and Lady GaGa. Jones takes the top spot this week with "Chasing Pirates" moving 3-1, but Boyle is fast approaching with "Wild Horses" sprinting 7-2, and GaGa's "Paparazzi" jumps 9-4.