Three days to break a habit?

I remember hearing that it takes three days to break a habit.  I wonder, is the inverse true?  I have worked out three of the last 4 days.  Will I now be more inclined to work out, rather than talk myself out of it?  I sure hope so!  I have already noticed a difference in my work out.  I was able to go a little longer today, and I felt stronger doing it!  My eating has been great this week.  I went to a friends for lunch this week, and I packed myself an awesome salad so that I could keep myself on track!  Now, if the snow would stop falling and I could get outside, I would be much happier!