There can be some iffy stuff, but depending on your settings/stations, you should be safe from it!
Well, I absolutely love Pandora. However, depending on your settings and stations people can be exposed to music where people: talk about sexual stuff, cuss, encourage drinking/drugs, etc. BUT you can change that! I mean if you put on a Disney station, there shouldn't be any inappropriate things and you can change the settings (my account then explicit content...) to block that stuff.
ALSO: if you want like extremely random songs (varying from new music to Frank Sinatra) type in Party in the USA :D Yeah, that's what I thought too, but it works! :D