I am very picky when it comes to music. I have to be able to feel the song and understand it. It has to have a good sound to it to of course. But I have a pretty ecclectic taste.

Lyrics or emotion the song conveys are very important to me. I can appreciate silly songs, but i prefer songs that have meaning to me.

A catchy melody, and a good lyrics.

The beat is what has me like a song - I'll listen to the words after I hear the beat.

If the lyrics move me, or if I feel they apply to me, or if the song is fun to sing.

Just the amount of delivery that the artist gives, the soul

the meaning in the lyrics of the song, plus a good melody.

1) Has to have at least a good singer, if not great. 2) has to be catchy and mostly easy to sing 3) has to have a bit in it that is either very low or very high or generally hard to sing, but the singer gets it perfectly 4) Harmonies are always good 5) has to have meaningful lyrics, ones that require you to have heard the song quite a few times before realising what it actually means, or that require thought to get the meaning from them.

Thats a fascinating question because the answer is "no one really knows". The "best" singers in the world technically are opera (most rock singers are terrible by classical standards) , the most "brilliant" music arrangements are from composers writing symphonies (not your 3 chord Red Hot Chili Peppers), yet so many still follow the White Stripes or Hives untouchably. After watching the movie "Walk the Line" theres a part where Johnny Cash goes to get a record deal the first time by playing gospel music and the executive says "If you were dying and had one last song to tell the world what your about, it would be this crap?" Thats a huge commonality in all hit songs, they communicate ALOT really clearly. Its very obvious what the artist is saying (take knockin on heavens door for a lyrical analogy). However music communicates with more than just lyrics too, think of the power of ACDC's back and black guitar riff, or the intense and dark reality of our world in Nirvana's Smells Like Teen Spirit. Music communicates in so many ways its hard to track them all and thats why there are no formulas for how to write hits. However one thing that is for certain is that you favorite music STRONGLY COMMUNICATES the exact feeling that you want and need, wither it's screaming guitar, seductive storytelling or just a plain old adrenaline rush.

a good beat something i can dance to

Good music and good lyrics which would touch on the realities of life.