The show is where Stinky trys out for the yahoo soda kid. When Stinky is on the roof throwing a bouncy ball, if you look in front of him, there is a billboard saying "Whaoo Soda, Just drink it." In the next shot of it, it says Yahoo has a great taste.
Haven't you ever been to a big city? Their billboards change every few seconds to get the maximum amount of advertising as possible. Since Stinky lives in New York that's obviously what happened!
Actually, I think you are seeing things. I just watched that episode, and neither my sister or I saw anything remotely like "Yahoo soda has a great taste". You need to get your eyes checked!!