One of my favorite copywriters -- whose ads and books I study almost every single day -- is the late Eugene Schwartz.

And one of the best lines he ever said (in a speech he gave to Phillips Publishing 13 years ago) was something to the effect of:

"If an ad doesn't have the word 'you' in it 100 times, I really don't like it very much."

In other words, the word "you" should be in your ad as much as possible. Not only to help the reader feel like you're talking directly to him or her