From Sharon Delaney on the Official Lucy List: "I saw a rumor floating around the internet that Lucy had been approached to do D'Anna on Caprica.  I asked, she answered, "Nope."

One of the articles that started the speculation:
 
Tuesday, February 9, 2010
Mega Buzz By MICKEY O'CONNOR AND ADAM BRYANT -  TV GUIDE

[...]

Will we ever see the world of Battlestar Galactica come crashing into Caprica? -- Tally
MICKEY: I will bet you one meeellion cubits that we will. Caprica executive producer Jane Espenson tells us that the new show will address the overlap through the backstory of the Final Five, who, as you remember, started their "lives" on Caprica. "If you actually do the math, the [human-Cylon] war starts about five years from where our characters are in Caprica," Espenson says. And what's this? The producers have already contacted Spartacus' Lucy Lawless about reprising the role of D'Anna on Caprica. Watch your back, Eric Stoltz!

[...]


News submitted by Barbara Davies.