I decided to listen to the "Top 100 songs on iTunes" list on Zune (they mirror the top 100, so subscribers can listen -- yes I resubscribed, I'm weak).
In any case, I've listened to 5 of the top 100 so far and 3 of them had that stupid auto-tune effect used by T-Pain, originally made popular by Cher. Of the Black Eyed Peas, Flo Rida, Lady Gaga, Miley Cyrus and Jamie Foxx (with T-Pain), I think the only ones that didn't use the effect were Lady Gaga and Miley Cyrus.
For those who don't know what I'm talking about, check out this spoof of auto-tuning.
I'm going to start calling this effect "auto detune", because it sounds so awful (except is very funny in the above).