I doubt that if you asked your clients what they buy from you that they'd answer, "Time."  Yet because (many of) you sell time to them, it is often the only thing that you measure with any rigor.

In 2010, Resolve to Measure What Your Clients Treasure.  Start by asking every client this question:

"How will you measure your satisfaction with us as we serve you?" 

Don't settle for an answer that depends completely on the end result.  Instead, press for answers like "By always keeping me up to date," and "Returning my phone calls promptly."

Once you've identified at least two things most of your clients want from you, begin to measure how well you're doing them.  Your clients already are.