I've refinance a number of times and this was an excellent experience. Some "do's" and "don'ts" :
Make sure you have all the information requested and available for faxing / e-mailing. Respond quickly and completely if you expect the agents to accomplish their job. Be pleasant and don't expect miracles. Remember they have other customers too and all of them want the same fast, efficient service.
Be patient and don't be afraid to ask questions. And finally, make sure that once you pull the trigger to refinance act quickly. Rates may not stay low for much longer.

As they say, get it done!