For all the time we spend here at Yahoo! Tech writing about the latest trends in digital music, you might think that the good-old Compact Disc was all but dead and buried. Ah, not quite, according to the latest research, which shows that CDs still account for the lion's share of music bought in the first half of 2009.

Indeed, only 35 percent music purchased in the U.S. in recent months came in digital form, according to the NPD Group, although that figure is well up from 20 percent back in 2007—and by 2010, CD and digital-music sales should be about 50-50, NPD researchers predict.

Interestingly enough, while CDs still rule the roost in terms of music sales, iTunes is the biggest music vendor in the U.S., accounting for 25 percent of all music sold—namely, as Fortune's Apple 2.0 blog points out, because several different brick-and-mortar and online retailers (such as Wal-Mart, Best Buy, Amazon, and Target) are fighting over the CD sales pie, while iTunes utterly dominates digital downloads (with a whopping 69 percent share, compared to just 8 percent for Amazon and 23 percent for everyone else).

Now, based on the trends outlined in the NPD report, it seems clear that physical CDs are, in fact, on the way out. If digital downloads and CDs do, in fact, end up splitting music sales by next year, I'd think that Compact Discs would account for just a sliver of the overall music market by, say, 2015 or so.

That said, for all the growth that digital music downloads are showing, I'm surprised that so many consumers are still happy to cough up extra cash to buy their tunes on CDs—especially given the sagging economy.

After all, why pay $13.99 and up for the latest Black Eyed Peas CD at Best Buy when you could snag it for $8.99 from Amazon's MP3 store? (Then again, never underestimate the appeal of the bargain CD bin at Wal-Mart.)

Quick show of hands: When was the last time you bought a physical music CD?