There are two VERY important reasons for cleaning up after yourself. You'll want to do this again, won't you? So, let's make sure everything is ready for the next brewing session.
And, if you have a roommate, wife, or Significant Other, you need to keep him or her happy. In homebrewing circles, the wife is often referred to as SWMBO (She Who Must Be Obeyed). Household peace will make your brewing, and beer, much more enjoyable.
I've seen a great deal about cleaning. What solutions, chemicals, equipment, brushes, etc to use. Again, use what you feel most comfortable with and what works best for you. I soak my bottle for several days in a weak bleach solution, and never use a brush. This works well for me.
Remember, keep everything sanitary!