What's up with Digital Evidence?

In our office, there is much talk about the admissibility of digital evidence in court.  One reason for this is that one of our bigger clients does not accept surveillance video on digital media, ie: hard drives, SD cards, etc.  This forces us to maintain an ever-mouldering and increasingly anachronistic and difficult to replace inventory of 8mm and DVC cameras.  Each of our investigators has to carry one of these in addition to whatever digital video equipment they may also use.
From our perspective, digital equipment trumps analog on almost every count.  It is smaller, more easily concealed, comes in a multitude of form factors from watches to pens to actual cameras, and you can use the storage media over and over again.  Its like a dream come true really. Still though, some clients are wary about diving into these pixel-y waters.  Why?
The short answer is that people think digital evidence can be tampered with, raises a billion chain of custody issues, and may not stand up to the ravagings of any particularly knowledgeable lawyer in court.  I'm not sure if this has any real ring of truth, as we have presented both analog and digital evidence without any credibility issues whatsoever, but the fears persist.
I read an interesting article on this recently, and there are a multitude of sources out there if you google the subject, but as far as digital video goes, here are some points where they all seem to concur:
  
The Definition of "Original" - for a writing or a recording, Federal Law states that an original is the thing itself, or any counterpart that is intended to have the same effect on the viewer or reader.  For example, an "original" of a photograph is the negative, or any print made directly from the negative without alteration. Simply put, if a copy, print, or alternative presentation of the data accurately reflects the original, it can also be considered original.

The Definition of "Duplicate" -   a reproduction of an original using a technique such as photography, re-recording, chemical reproduction, or a similar technique which produces a copy of the original.  (this gets into some interestingly fuzzy territory in my book)

Chain of Custody for digital photos and video -

• Burn a non-rewriteable CD or DVD directly from the media using a stand alone burner or a computer (although the stand alone method is preferrable)
• Make two "copies" of the evidence.  Place one in a file or secure location where it will not be tampered with or altered (a restricted access area would be ideal)  and be sure to mark it with the date and the initials of the person who made it or some similar identifier.  The other copy should be used when you need to review or examine the photo or video, so that there remains one copy that has been untouched after it was made. 
• Keep a log anytime you move or handle the evidence.  Make sure you note who does this, the date, and reason.  
• Remember that a CD or DVD containing video or photos is essentially no different than any other piece of analog or physical evidence, and the same rules for securing it apply. Everything CAN be tampered with, but the point of having evidenciary rules and chain of custody procedures is to maintain the integrity of the evidence.
• You should find out what specific rules or guidelines are operating in your state or region.  Expert pages has a good listing of these at: http://expertpages.com/news/state_rules_of_evidence.htm

 There is a lot of reading to be done on the subject.  The best article I read was in PI Magazine  , but there are hundreds of other resources as well that I was able to find in just a cursory search.  As we go forward, digital video, audio, and photographs are likely to be the new evidenciary standard for PI's everywhere, as there will really be a limited field of other options for camera and recording equipment.  Therefore, it is best to get in some good habits now with regard to keeping this kind of evidence secure and intact.  Don't want to get caught with your pants down!