When stocks like P drop like this there's a three day rule that is fairly reliable: Buy on the third day following the news - the risk is minimal at that point. That would mean late Wednesday or early Thursday.
As one content analyst said on Bloomberg to paraphrase. The drop of P is overdone.
They have now become the playing field turf for Google, Apple, and Sirius. What do you think the future looks like for Pandora, keeping in mind that they don't even make a profit yet? All of the above make big money, compete directly with P, and control access to the store. If you buy this one, you best move in and out in the same day. She is a gonner, the question is not if, the question is how long.
Sentiment: Strong Sell
I have Sirius. It's over $10 a month. Google is $10 per month. P with no ads is 3.99 a month. I have Pandora ad-free and I'm not going to pay more just for music. AAPL is not ad free at all and if they have an ad free service, knowing AAPL it'll be expensive. So pandora is probably in the sweet spot On top of that, given AAPLs track record of such type of ventures, the odds are fairly high that iRadio will fail after some period of time and just cannibalize iTunes. In hardware they're so slow they're behind Samsung.
Anyway, II suggest you start or add to your short tomorrow or Thursday.