Holiday season sales: There’s no stopping Susan Boyle

British singing sensation Susan Boyle continues her dominance of the U.S. pop charts, with her orchestral-lite takes on boomer standards hitting a sweet spot with music buyers. In three weeks, her “I Dreamed a Dream” has sold a stunning 1.8 million copies in the U.S., according to Nielsen SoundScan, surpassing 2009 releases from such mega-stars as Eminem and Green Day, and even overtaking another TV-made phenomena –  the soundtrack to “Hannah Montana: The Movie,” which has sold 1.7 million copies since its release in the spring.

How far can Boyle go? Expect her sales to coast through the holidays. It will be worth watching to see what happens in January, when music sales typically plummet. With comfy-soft renditions of “Daydream Believer,” “Amazing Grace” and more, Boyle’s “I Dreamed a Dream” is clearly built for holiday-timed sales, and it’s taking full advantage.

Her album hit another milestone this week too, racking up an additional 582,000 copies sold. Billboard reports that “I Dreamed a Dream” is the first album by a woman to sell 500,000 copies in each of its first three weeks since SoundScan began tracking data in 1991. If Boyle’s pace stays relatively steady, and with three sales weeks left in 2009, including the two biggest of the year, her album could top 3 million copies sold and quite possibly become the year’s top seller. But one week at a time.