You may have heard or noticed by chance, as I did, that Apple in the last few days has extended song previews from 30 to 90 (!) seconds in the iTunes store. The first time I noticed it, I did a double-take, thinking I had somehow accidentally bought the song.
One undesirable side effect that I noticed: In some cases, depending on the song length and your preferences settings in Last.fm's Audio Scrobbler, the preview may be long enough to count the preview as a full play and add it to your profile on Last.fm. I've got my Scrobbler set at 75 percent to count a song as a full play, and that was enough to add two preview plays to my profile. For the stat-obsessed, this could be quite the nagging annoyance.
So, the result was Bananarama's "Baby It's Christmas" and Double You and Friends' cover of "Do They Know It's Christmas" from Super Dance Christmas Party Vol. 3 showed up on my Last.fm history merely from listening to the iTunes samples. I deleted the scrobbles on principle (not because those song selections are anything of which one would be ashamed, of course).
On the plus side, a 90-second sample is a much better taste of a song — you're less likely to get those clueless samples that only feature the intro of a song or some middle breakdown that is unrepresentative of the whole — and an unexpectedly generous move on Apple's part.