I love Pandora because I can type in a song and get 100 other just like it, so its like my own digitally created Itunes playlist everytime. Slacker is more like a traditional radio station
i like em both. pandora gives me some artists that don't make sense to me though. i have a Slightly Stoopid channel and i keep getting effing jack johnson on it! slacker rocks b/c of (1) the ability to cache and (2) the preset genre stations, which are pretty specific. i wish pandora would get those. on the other hand, pandora loads much faster.