What is Net Worth Worth?

It seems like pretty much a given for personal finance bloggers to provide a net worth, and since I'm a big numbers fan, it was one of the first things that I added to my own site. But trying to calculate it did raise some questions for me about it's real value. Sure it's useful as a yardstick, and if I stay consistent in how I calculate my own it can be a great comparison tool from month to month. But considering all the questions I came up with while I was calculating my own, I'm not sure it's a good way to compare against others. I'd be curious to see what some people decided on the following when calculating their own worth.

• Does the car count? I chose to include mine because it's newish and represents a good chunk of my assets at this point. Beyond that, on one hand it's a depreciating asset, on the other, if I was in a real crunch I could sell it for some good money. So which way to go? I'm thinking about leaving it while I pay off the loan and getting rid of it once I'm done, but that'll mean a drop.
• What about other belongings? I didn't think I had anything else quite as valuable and easy to sell, but all of my furniture taken together, for example, might be worth $1000-2000. I chose to leave it out.
• How do you classify retirement funds that are invested in mutual funds, stocks, etc... are they all lumped under retirement, separated into investment type, or something else?
• Where do employee stock purchase plan stocks go? They're not really just like "stock" because of the tax implications, if nothing else, but I don't see another good category for them. Also, they accrue for 6 months before a purchase date, so they will cause me to have a bump every 6 months.
  
• What do you include under credit card debt? Are revolving balances you pay off every month included? Mine seem to vary a lot so I chose to include only my one revolving balance (it's at a lower APR than my bank account, don't worry).